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Toyota · Known Issues

2001 Toyota 4Runner Problems: 10 Known Issues

2001 model year · NHTSA recalls, manufacturer TSBs, and owner forum reports · Updated September 2026

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Issue summary

According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2001 Toyota 4Runner has 10 documented known issues, with 3 rated critical. The most serious are Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid ($300-$4,500 repair), 4WD Transfer Case Actuator Seizure from Infrequent Use Preventing 4HI/4LO Engagement ($600-$2,200 repair) and Lower Ball Joint Wear/Separation on 3rd-Gen Front Suspension ($500-$1,200 repair). Across all issues with published estimates, repair costs range from $15 to $4,500. DIY maintenance guides at au7o.io.

In This Article

  • 4Runner Cooling2
  • 4Runner Drivetrain1
  • 4Runner Suspension1
  • 4Runner Emissions3
  • 4Runner Steering1
  • 4Runner Engine1
  • 4Runner Fuel System1
  • Recalls7
  • FAQ
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In This Article

  • Cooling2
  • Drivetrain1
  • Suspension1
  • Emissions3
Steering
1
  • Engine1
  • Fuel System1
  • Recalls7
  • FAQ
  • All 10 Known Issues

    Filter:
    ALL YEARS202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999199819971996199519941993199219911990

    When Issues Typically Appear

    4WD Transfer Case Actuator Seizure from Infrequent Use Preventing 4HI/4LO Engagement
    70K-200K
    Lower Ball Joint Wear/Separation on 3rd-Gen Front Suspension
    80K-200K
    Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid
    120K-220K
    063K125K188K250K mi

    On the 2000-2002 Toyota 4Runner, on 3rd-generation automatic 4Runners, the internal transmission cooler inside the radiator can rupture and allow coolant and ATF to mix, commonly called the 'pink milkshake.' Once fluids cross-contaminate, the transmission can begin slipping, shuddering, or fail completely. This is heavily documented in owner forums and repair discussions because the damage can escalate quickly if not caught early.

    Common Symptoms

    • strawberry-milkshake fluid in radiator or overflow bottle
    • milky or foamy ATF
    • transmission slipping
    • delayed shifting
    • overheating
    • coolant loss

    How to Fix

    Inspect the radiator and transmission fluid condition regularly; milky pink fluid in the radiator or transmission dipstick is a major warning sign. Preventive replacement of the radiator is common on aging vehicles, and many owners bypass the internal cooler or add an external transmission cooler. If contamination has already occurred, the radiator must be replaced and the transmission may require repeated flushing or full rebuild/replacement.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Denso 221-0508 First Time Fit radiator with transmission oil cooler

      preventive or confirmed radiator/internal-cooler replacement before reconnecting clean cooling and transmission circuits Fitment/availability: 1996-2002 Toyota 4Runner; listing explicitly includes the internal transmission oil cooler and…

      FinditParts

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$300 - $4,500

    Research This Issue

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    Community Reported
    High Confidence

    On the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE V6, the 5VZ-FE water pump is driven off, and buried behind, the timing belt. Its shaft seal wears with age and mileage and coolant begins seeping from the pump's weep hole — the designed early-warning drip before the bearing fails. Because accessing the pump requires the same teardown as a timing-belt job, owners search heavily for how to combine the two. Ignoring the weep can progress to bearing failure, coolant starvation, and (since the 5VZ is an interference engine) a snapped-belt catastrophe if the belt is also neglected.

    Common Symptoms

    • Coolant drip / crust from the water pump weep hole
    • Low coolant level and mild overheating
    • Coolant smell after driving
    • Whine or wobble from the timing-belt area (bearing wear)
    • Pink/green residue on the lower front of the engine

    How to Fix

    Replace the water pump whenever the timing belt is serviced (Toyota interval ~90k miles), and vice-versa. Do the belt, tensioner, and idler pulleys at the same time — the labor is identical. Key parts: Aisin/Toyota water pump assembly 16100-69398-83; timing belt 13568-YZZ03 (Aisin), hydraulic tensioner and idler/tensioner bearings, thermostat 90916-03075, and new coolant. Complete OEM/Aisin timing + water-pump kits are widely available (~$150-250 in parts); shop labor typically brings it to $500-900.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • AISIN TKT-025 timing-belt kit with water pump, bypass tube and hydraulic tensioner

      complete overlapping water-pump and timing-belt service kit Fitment/availability: 1996-2002 Toyota 4Runner 3.4L V6 5VZ-FE; retailer specifies hydraulic tensioner and bypass tube, so confirm oil-cooler plumbing before purchase Fitment/ava…

      PartsGeek

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$150 - $900

    Research This Issue

    GoogleRedditYouTubeNHTSA
    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 2000-2009 Toyota 4Runner, a well-known 4Runner problem is the transfer case shift actuator sticking or seizing, especially on trucks that spend years in 2WD or full-time mode without regular 4WD cycling. Owners report flashing 4WD lights, inability to engage or disengage 4HI/4LO, and in some cases being stuck in one mode. The actuator motor and internal position switches can corrode or gum up, and on many models the actuator is integrated in a way that makes repair labor-intensive.

    Common Symptoms

    • Flashing 4WD indicator
    • 4HI will not engage
    • 4LO will not engage
    • Stuck in 4WD or stuck in 2WD
    • Center differential lock will not engage
    • No actuator motor sound
    • Beeping when attempting 4LO shift

    How to Fix

    Confirm the issue by checking whether the transfer case actuator motor responds to commands, verifying switch inputs, and scanning for 4WD control faults where applicable. Sometimes repeated cycling and fluid service can temporarily free a sticky actuator, but many cases require actuator replacement or transfer case removal and disassembly to clean and reseal the mechanism. Regular monthly engagement of 4HI and 4LO is widely recommended to prevent recurrence.

    Owner tips & cautions

    • TipCycle 4HI and 4LO at least monthly, even if you do not off-road; this is the most common owner advice to keep the actuator from sticking.
    • TipChange transfer case fluid before condemning the actuator if engagement is slow or intermittent, but do not expect fluid alone to fix a fully seized unit.
    Typical repair cost:$600 - $2,200

    Research This Issue

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    Community Reported
    High Confidence

    On the 2000-2002 Toyota 4Runner, on late 3rd-generation 4Runners, the front lower ball joints are a well-documented failure point and can develop excessive play or separate without much warning. Toyota issued a safety recall because separation can cause loss of steering control and front wheel collapse. Owners commonly report clunking, wandering, uneven tire wear, or sudden suspension failure if the joints are neglected.

    Common Symptoms

    • front-end clunk over bumps
    • loose or wandering steering
    • uneven front tire wear
    • popping noise while turning
    • sudden front wheel collapse in severe cases

    How to Fix

    Inspect the lower ball joints for play, torn boots, grease loss, and looseness at every front-end service, especially on higher-mileage vehicles. Replace both lower ball joints with updated OEM Toyota parts and new hardware; many owners also replace the tie-rod ends if wear is present. An alignment should be performed after repair.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 43340-39465 front-left lower ball joint

      left safety-critical joint replacement after inspection Fitment/availability: front driver side 1996-2002 Toyota 4Runner 2.7L or 3.4L; covers the full 2000-2002 record Fitment/availability: ships in 1-3 business days and Add to Cart live…

      ToyotaPartsDeal
    • Genuine Toyota 43330-39585 front-right lower ball joint

      right safety-critical joint replacement after inspection Fitment/availability: front passenger side 1996-2002 Toyota 4Runner 2.7L or 3.4L; covers the full 2000-2002 record Fitment/availability: ships in 1-3 business days and Add to Cart …

      ToyotaPartsNow

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$500 - $1,200

    Research This Issue

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    Community Reported
    High Confidence

    On the 2000-2009 Toyota 4Runner, later 3rd-gen and 4th-gen 4Runners use a wide-band Air-Fuel Ratio (A/F) sensor as the upstream (Bank 1 Sensor 1) oxygen sensor. With age and heat cycling the sensor's internal heater or element degrades, setting codes such as P0125 (insufficient coolant temp for closed loop / A-F feedback), P1130 (A-F sensor range/performance), or P0135 (heater circuit). Symptoms include poor fuel economy, hesitation, and a check engine light. It's a very common high-mileage sensor replacement and a frequent search topic.

    Common Symptoms

    • Check engine light P0125, P1130, or P0135
    • Reduced fuel economy
    • Hesitation or slight rough running
    • Long time to reach closed loop when cold
    • Failed emissions readiness monitor

    How to Fix

    Confirm with live data (A/F sensor slow to respond, or heater resistance out of range) and check the sensor connector/harness for corrosion before condemning the sensor. Replace with a genuine Denso/Toyota A/F sensor — aftermarket units frequently cause repeat faults on Toyota's sensitive A/F circuit. For the 4th-gen 4.0L, the upstream Bank 1 A/F sensor is Toyota 89467-series (e.g., Denso 234-9055 / Toyota 89467-60010); verify the exact part against your year/engine. Parts $120-350; DIY-friendly with an O2 socket.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 89467-35011 front air-fuel ratio sensor

      2000-2002 5VZ-FE Bank 1 upstream branch after circuit and live-data diagnosis Fitment/availability: 1998-2002 Toyota 4Runner including 3.4L 5VZ-FE; catalog Q&A specifically identifies this part for 2000 4Runner upstream Bank 1 and it sup…

      ToyotaPartsDeal
    • Genuine Toyota 89467-60010 air-fuel ratio sensor

      early fourth-generation upstream branch after bank-specific heater/performance diagnosis Fitment/availability: 2003-2005 Toyota 4Runner 4.0L 1GR-FE and 4.7L 2UZ-FE; catalog shows quantity two, so confirm the failed bank and VIN before or…

      ToyotaPartsDeal

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$120 - $400

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 1999-2009 Toyota 4Runner, as 4Runners accumulate miles, the catalytic converter loses efficiency and the ECU sets P0420 (Bank 1) and/or P0430 (Bank 2) when the downstream O2 sensor starts to mirror the upstream sensor. On the 4th-gen 1GR-FE, the primary cats are integrated into the exhaust manifolds, which makes them prone to cracking and internal breakdown with heat and age — a frequently searched and relatively expensive repair. Misfires, exhaust leaks, or a failing rear O2 sensor can also trip the code, so diagnosis before parts replacement matters.

    Common Symptoms

    • Check engine light with P0420 and/or P0430
    • Passed-then-failed emissions / smog test
    • Slight loss of power or fuel economy at high mileage
    • Rattle from the exhaust manifold/cat (broken internal substrate)
    • Sulfur/rotten-egg smell

    How to Fix

    Diagnose before buying a cat: scan for misfire codes (P030x/P0300), check for exhaust leaks upstream, and compare upstream vs downstream O2/A-F sensor waveforms. If sensors and exhaust are healthy and the downstream signal tracks the upstream, replace the failed converter. On 4th-gen 4.0L trucks the failure is usually the passenger-side (Bank 1) manifold-integrated cat. Use OEM or a high-quality CARB-compliant converter; a common contributing fix is the Bank 1 Sensor 2 (downstream) O2 sensor (use Denso). Sensor-only fixes run $100-300; converter replacement is the expensive path.

    Typical repair cost:$150 - $2,500

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 1996-2009 Toyota 4Runner, eVAP faults (P0440 general malfunction, P0441 incorrect purge flow, P0446 vent control circuit) are among the most common check-engine codes on 3rd- and 4th-gen 4Runners. Toyota issued service bulletin EG013-03 covering these codes across 4Runner/Camry/Tacoma. The frequent culprit is a Vacuum Switching Valve (VSV) — especially the canister-closed-valve VSV near the charcoal canister mounted above the spare tire — which sticks when charcoal fines migrate into it. A loose/failed gas cap or a cracked canister can also trigger the codes.

    Common Symptoms

    • Check engine light P0440, P0441, or P0446
    • No driveability change (emissions monitor fault only)
    • Fuel smell in some cracked-canister cases
    • Failed emissions readiness / smog test
    • VSV does not click when 12V applied

    How to Fix

    Start cheap: verify the fuel cap seals and clicks. Then test the VSVs (there are typically three — two under the hood and one at the canister): apply 12V and listen for the click and check that airflow switches; a stuck/silent VSV is the failed part and is far cheaper than the whole canister. Replace the failed VSV or, if the charcoal canister is shedding/cracked, replace the canister. Use genuine Toyota EVAP parts to pass monitors reliably. Gas cap ~$15-40; VSV ~$30-120; full charcoal canister $150-500.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 25860-75160 No.2 vacuum switching valve

      third-generation valve branch only after functional and circuit diagnosis Fitment/availability: 1996-2001 Toyota 4Runner 2.7L 3RZ-FE or 3.4L 5VZ-FE; catalog identifies it as No.2 VSV Fitment/availability: ships in 1 business day and Add …

      ToyotaPartsDeal
    • Genuine Toyota 90910-12264 charcoal-canister vacuum switching valve

      late third-generation canister-valve branch after code-directed testing Fitment/availability: 2000-2002 Toyota 4Runner 2.7L 3RZ-FE or 3.4L 5VZ-FE; catalog labels it FOR CHARCOAL CANISTER Fitment/availability: ships in 1 business day and …

      ToyotaPartsDeal
    • Genuine Toyota 77300-47010 fuel cap

      first repair branch when seal damage or a cap leak is proven Fitment/availability: 2004-2009 Toyota 4Runner 4.0L or 4.7L; exact California/federal configuration should be confirmed Fitment/availability: ships in 1-3 business days and Add…

      ToyotaPartsNow
    • Genuine Toyota 25860-31010 purge vacuum switching valve

      fourth-generation purge-valve branch after bidirectional and circuit testing Fitment/availability: 2003-2009 Toyota 4Runner 4.0L 1GR-FE or 4.7L 2UZ-FE; superseded by 25860-0P010 Fitment/availability: ships in 1-3 business days and Add to…

      ToyotaPartsNow
    • Genuine Toyota 77740-35490 charcoal canister assembly

      early fourth-generation canister branch only after smoke/flow testing proves canister failure Fitment/availability: 2003-2005 Toyota 4Runner Fitment/availability: ships in 1-2 business days and Add to Cart live when reviewed

      ToyotaPartsDeal
    • Genuine Toyota 77740-35530 charcoal canister assembly

      late fourth-generation canister branch only after smoke/flow testing proves canister failure Fitment/availability: 2006-2009 Toyota 4Runner 4.0L or 4.7L; replaced by 77740-35531 Fitment/availability: Add to Cart live when reviewed

      ToyotaPartsDeal
    • Genuine Toyota 77310-12140 fuel cap for early third-generation branch

      early third-generation cap branch after a cap leak is proven Fitment/availability: 1985-1998 Toyota 4Runner; covers only the 1996-1998 portion of this issue and does not establish 1999 fitment; confirm VIN before purchase Fitment/availab…

      ToyotaPartsDeal

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$15 - $500

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 1996-2009 Toyota 4Runner, 3rd- and 4th-gen 4Runners commonly develop power-steering whine and reddish ATF leaks with age. A whine is often not the pump itself but old fluid or a clogged filter screen in the bottom of the PS reservoir; leaks frequently originate at the union-bolt gaskets, high-pressure/return hoses, the pump shaft seal, or the steering rack. Heat cooks the pump seals, and some owners report rebuilding a pump twice from seal failure. Note: the 4Runner PS system uses ATF (Dexron), not conventional power-steering fluid — using the wrong fluid swells seals and causes failure.

    Common Symptoms

    • Whining noise that rises with steering effort / RPM
    • Reddish ATF puddle under the front of the truck
    • Low PS fluid level
    • Stiff or groaning steering when cold
    • Foamy/aerated fluid in the reservoir

    How to Fix

    For whine, first siphon the reservoir, clean the internal filter screen with brake cleaner, and refill with fresh Dexron II/III ATF — this alone often cures the noise. For leaks, pinpoint the source: replace the union-bolt sealing washers/gaskets for pump-fitting leaks, replace worn high-pressure/return hoses, or reseal/replace the pump if the shaft seal is leaking. Always refill with ATF, never generic PS fluid. Cleaning/flush is nearly free; hoses/gaskets $30-120; a replacement pump runs $120-350 in parts.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 44320-35490 power steering vane pump

      third-generation pump branch only after restriction, hose leaks and aeration are ruled out Fitment/availability: 1996-2002 Toyota 4Runner; catalog identifies the 3.4L branch and confirms reservoir included for the inspected 2000 applicat…

      ToyotaPartsDeal
    • Genuine Toyota 44410-35570 power steering pressure hose

      late third-generation high-pressure leak branch after source localization Fitment/availability: 3.4L Toyota 4Runner pressure line; stored research scopes it to 1999-2002 and the direct dealer page confirms the VZN18# application Fitment/…

      Toyota Parts Overstock / Lakeland Toyota
    • Genuine Toyota 44327-30030 pressure-port gasket

      new sealing washer branch when the matching pressure connection is opened Fitment/availability: Toyota pressure-port sealing gasket; verify exact joint and required quantity by VIN/service diagram before disturbing the pressure fitting F…

      ToyotaPartsDeal
    • Valvoline DEX/MERC automatic transmission fluid, 1 gallon

      screen-clean/flush/refill consumable after leaks are repaired Fitment/availability: fluid manufacturer lists use where Dexron III is specified; use only where the exact 4Runner owner's manual calls for Dexron II/III ATF in power steering…

      Walmart

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$20 - $500

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE V6, on the 3rd-gen 4Runner's 3.4L 5VZ-FE V6, the two knock sensors sit in the engine valley beneath the upper and lower intake manifolds, and their sub-wiring harness bakes over time. The harness insulation becomes brittle and crumbles, opening the circuit and setting P0325 (knock sensor 1 circuit) and/or P0330 (knock sensor 2 circuit). The ECU then pulls timing, hurting fuel economy and power. It is a very high-demand repair topic because the fix is buried under the intake, and because the ECU is extremely sensitive to sensor signal quality.

    Common Symptoms

    • Check engine light with P0325 and/or P0330
    • Noticeably reduced fuel economy
    • Slight loss of power / sluggish acceleration
    • Brittle, crumbling wiring found under the intake manifold
    • Code returns after aftermarket sensor install

    How to Fix

    Remove the upper and lower intake manifolds and replace BOTH knock sensors plus the knock-sensor sub-harness. Use OEM/Denso sensors only — aftermarket knock sensors very frequently fail to clear the code, forcing you to redo the whole labor-intensive job. Key parts: knock-sensor sub-harness Toyota 82219-34010; two Denso knock sensors (Denso 89615-series); new upper and lower intake manifold gaskets and a fresh coolant fill. Budget roughly $150-300 in genuine parts (harness + 2 sensors + gaskets), or ~$400-900 done at a shop given the intake teardown labor.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 82219-34010 5VZ-FE knock-sensor sub-harness

      heat-aged valley sub-harness replaced during diagnosed knock-circuit repair Fitment/availability: 1996-2002 Toyota 4Runner 3.4L 5VZ-FE according to the retailer Fitment/availability: quantity control and purchase path live when reviewed

      YotaShop
    • Genuine Toyota/Denso 89615-12090 knock control sensor

      current superseding sensor for a bank whose sensor is confirmed faulty Fitment/availability: 1996-2002 Toyota 4Runner 3.4L 5VZ-FE in the Toyota catalog; Denso manufacturer note; one sensor per listing and quantity must follow diagnosis F…

      ToyotaPartsDeal

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$150 - $900

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026

    On the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE V6, the 3.4L 5VZ-FE uses a rotary-solenoid Idle Air Control (IAC) valve on the throttle body to manage idle. Over high mileage the IAC passages and valve clog with carbon and oil deposits, producing erratic idle (hunting between ~700 and ~1200 RPM), high idle, or low idle that shakes and stalls — often stalling at stops or when the A/C compressor loads the engine. It's a very frequent, well-documented maintenance item for 5VZ-FE 4Runners/Tacomas and commonly sets P0505 (idle control system malfunction).

    Common Symptoms

    • Erratic/hunting idle (surging up and down)
    • High idle when warm or low idle that shakes
    • Stalling at stops or when A/C engages
    • Check engine light P0505 (or P0506/P0507)
    • Rough idle after cold start

    How to Fix

    Remove and clean the IAC valve and throttle body bore/passages with throttle-body cleaner; inspect the connector and harness for corrosion or broken pins. Cleaning frequently restores normal idle, but a worn valve may need replacement — use an OEM/Denso IAC valve, as non-OEM units are a frequent cause of repeat P0505. Also rule out vacuum leaks, which mimic the same code. Cleaning is nearly free; an OEM IAC valve runs roughly $100-300, DIY-friendly.

    What you need to fix it

    Only diagnosis- and fitment-reviewed repair parts are linked here.

    • Genuine Toyota 22270-62050 idle air control valve

      conditional valve replacement after leak, circuit and cleaning tests fail Fitment/availability: retailer explicitly lists 1996-2001 Toyota 4Runner V6 3.4L 5VZ-FE; not approved here for 2002 without VIN confirmation Fitment/availability: …

      YotaShop
    • Genuine Toyota 22215-62180 IAC valve gasket

      new seal when the applicable IAC valve is removed for cleaning or replacement Fitment/availability: retailer explicitly lists 1996-2000 Toyota 4Runner 3.4L 5VZ-FE; confirm VIN for 2001 and do not apply to 2002 without catalog confirmatio…

      YotaShop

    As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

    Typical repair cost:$20 - $350

    Research This Issue

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    Community Reported
    Medium ConfidenceVerifiedReviewed Jul 2026
    NHTSA Recalls7 recalls

    SEATS:FRONT ASSEMBLY:SEAT HEATER/COOLER

    Southeast Toyota Distributors, LLC (SET) is recalling certain model year 2010-2011 Prius and Corolla, 2009-2011 Venza, 2006-2010 Avalon, 2007-2010 FJ Cruiser, 2005-2011 Sienna and Sequoia, 2006-2011 Tacoma 4x2 and 4x4, Camry, Highlander, Tundra 4x2 and 4x4, and 2007-2011 Rav4 and 4Runner. The affected vehicles may experience compression of the seat cushion which may damage the seat heater wiring.

    Campaign #14V74300019/11/2014

    SEATS:FRONT ASSEMBLY:SEAT HEATER/COOLER

    Southeast Toyota Distributors, LLC (SET) is recalling certain 2005-2011 4Runner, Highlander, Sequoia, and Sienna, 2005-2010 Avalon and Tundra, 2006-2008 Camry Solara, 2006-2010 Highlander hybrid, 2006-2011 Rav4 and Tacoma, 2007-2010 FJ Cruiser, 2007-2011 Camry hybrid, 2009-2010 Venza, 2010-2012 Prius, 1988-1990 and 2005-2010 Camry, and 1989 and 2009-2010 Corolla vehicles equipped with aftermarket accessory seat heaters with a copper strand heating element. The electrical wiring in the seat heaters may be damaged when the seat cushion is compressed.

    Campaign #16V39600002/06/2016

    AIR BAGS:FRONTAL:SENSOR/CONTROL MODULE-INACTIVE

    Southeast Toyota Distributors, LLC (SET) is recalling certain models interspersed through model years 2009 through 2013 as follows: model year 2009-2012 Tacoma, 4Runner, Camry, Camry Hybrid, Prius, and RAV4; model year 2009-2010 Avalon, FJ Cruiser, and Highlander Hybrid; model year 2010-2013 model year Corolla, Sienna and Tundra; model year 2009-2013 Highlander and Venza; model year 2012 Prius V; and model year 2010-2012 Sequoia. During modification by SET to include accessories such as leather seat covers, seat heaters or headrest DVD systems, these vehicles may not have had the passenger seat occupant sensing system calibration tested. Without passing the calibration test, the occupant sensing system may not operate as designed.

    Campaign #13V01400016/01/2013

    VEHICLE SPEED CONTROL:ACCELERATOR PEDAL

    TOYOTA IS RECALLING CERTAIN MODEL YEAR 2008 THROUGH 2011 LEXUS LX570, 2003 THROUGH 2009 TOYOTA 4RUNNER, AND 2006 THROUGH 2010 RAV4 VEHICLES. THE ACCELERATOR PEDAL CAN GET STUCK IN THE WIDE OPEN POSITION DUE TO ITS BEING TRAPPED BY AN UNSECURED OR INCOMPATIBLE DRIVER'S FLOOR MAT.

    Campaign #11V11300024/02/2011

    AIR BAGS:SIDE/WINDOW

    Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2003-2006 Toyota Land Cruiser and Lexus LX470, 2005-2006 Toyota Tundra and Sequoia, 2004-2006 Toyota 4Runner and Lexus GX470 vehicles equipped with side curtain-shield-air bags. The affected vehicles have an air bag control module that may be improperly programmed, causing the side curtain-shield-air bags to deploy inadvertently.

    Campaign #16V06500005/02/2016

    + 2 more recalls. Check all on NHTSA.gov

    Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.

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    Frequently Asked Questions

    What are the most common Toyota 4Runner problems?

    According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2001 Toyota 4Runner has 10 documented issues. The most frequently reported are: Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid, 4WD Transfer Case Actuator Seizure from Infrequent Use Preventing 4HI/4LO Engagement, Lower Ball Joint Wear/Separation on 3rd-Gen Front Suspension. Of these, 3 are rated critical and should be addressed promptly.

    Is the Toyota 4Runner reliable?

    The 2001 Toyota 4Runner has 10 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 3 issues are rated critical: Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid and 4WD Transfer Case Actuator Seizure from Infrequent Use Preventing 4HI/4LO Engagement and Lower Ball Joint Wear/Separation on 3rd-Gen Front Suspension. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

    How much does it cost to fix common Toyota 4Runner problems?

    Repair costs for known Toyota 4Runner issues range from $15 to $4,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid, typically costs $300-$4,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

    What is the 2000-2002 Toyota 4Runner Pink Milkshake Radiator Failure Mixing Coolant and Automatic Transmission Fluid?

    On 3rd-generation automatic 4Runners, the internal transmission cooler inside the radiator can rupture and allow coolant and ATF to mix, commonly called the 'pink milkshake.' Once fluids cross-contaminate, the transmission can begin slipping, shuddering, or fail completely. This… Repairs typically run $300-$4,500. Severity: high.

    What is the 2000-2009 Toyota 4Runner 4WD Transfer Case Actuator Seizure from Infrequent Use Preventing 4HI/4LO Engagement?

    A well-known 4Runner problem is the transfer case shift actuator sticking or seizing, especially on trucks that spend years in 2WD or full-time mode without regular 4WD cycling. Owners report flashing 4WD lights, inability to engage or disengage 4HI/4LO, and in some cases being s… Repairs typically run $600-$2,200. Severity: high.

    What is the 2000-2002 Toyota 4Runner Lower Ball Joint Wear/Separation on 3rd-Gen Front Suspension?

    On late 3rd-generation 4Runners, the front lower ball joints are a well-documented failure point and can develop excessive play or separate without much warning. Toyota issued a safety recall because separation can cause loss of steering control and front wheel collapse. Owners c… Repairs typically run $500-$1,200. Severity: high.

    What is the 1996-2009 Toyota 4Runner Power Steering Pump / System Leak & Whine — Reservoir Screen Clog and Seal Failure?

    3rd- and 4th-gen 4Runners commonly develop power-steering whine and reddish ATF leaks with age. A whine is often not the pump itself but old fluid or a clogged filter screen in the bottom of the PS reservoir; leaks frequently originate at the union-bolt gaskets, high-pressure/ret… Repairs typically run $20-$500. Severity: medium.

    What is the 2000-2009 Toyota 4Runner Air-Fuel Ratio (A/F) Sensor Bank 1 Sensor 1 Failure (P0125 / P1130 / P0135) — Heater Circuit / Slow Response?

    Later 3rd-gen and 4th-gen 4Runners use a wide-band Air-Fuel Ratio (A/F) sensor as the upstream (Bank 1 Sensor 1) oxygen sensor. With age and heat cycling the sensor's internal heater or element degrades, setting codes such as P0125 (insufficient coolant temp for closed loop / A-F… Repairs typically run $120-$400. Severity: medium.

    What is the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE Water Pump Weep Leak — Replace With Timing Belt Service?

    The 5VZ-FE water pump is driven off, and buried behind, the timing belt. Its shaft seal wears with age and mileage and coolant begins seeping from the pump's weep hole — the designed early-warning drip before the bearing fails. Because accessing the pump requires the same teardow… Repairs typically run $150-$900. Severity: medium.

    What is the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE Knock Sensor & Sub-Harness Failure (P0325/P0330) — Brittle Harness Under Intake?

    On the 3rd-gen 4Runner's 3.4L 5VZ-FE V6, the two knock sensors sit in the engine valley beneath the upper and lower intake manifolds, and their sub-wiring harness bakes over time. The harness insulation becomes brittle and crumbles, opening the circuit and setting P0325 (knock se… Repairs typically run $150-$900. Severity: medium.

    What is the 1999-2009 Toyota 4Runner Catalytic Converter Efficiency Below Threshold (P0420 / P0430) — Aging or Manifold-Integrated Cats?

    As 4Runners accumulate miles, the catalytic converter loses efficiency and the ECU sets P0420 (Bank 1) and/or P0430 (Bank 2) when the downstream O2 sensor starts to mirror the upstream sensor. On the 4th-gen 1GR-FE, the primary cats are integrated into the exhaust manifolds, whic… Repairs typically run $150-$2,500. Severity: medium.

    What is the 1996-2002 Toyota 4Runner 3.4L 5VZ-FE Idle Air Control (IAC) Valve Carbon Fouling — Rough/Surging Idle, Stalling (P0505)?

    The 3.4L 5VZ-FE uses a rotary-solenoid Idle Air Control (IAC) valve on the throttle body to manage idle. Over high mileage the IAC passages and valve clog with carbon and oil deposits, producing erratic idle (hunting between ~700 and ~1200 RPM), high idle, or low idle that shakes… Repairs typically run $20-$350. Severity: low.

    What is the 1996-2009 Toyota 4Runner EVAP System Leak — Charcoal Canister / Vacuum Switching Valve (VSV) Failure (P0440 / P0441 / P0446)?

    EVAP faults (P0440 general malfunction, P0441 incorrect purge flow, P0446 vent control circuit) are among the most common check-engine codes on 3rd- and 4th-gen 4Runners. Toyota issued service bulletin EG013-03 covering these codes across 4Runner/Camry/Tacoma. The frequent culpri… Repairs typically run $15-$500. Severity: low.

    Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.

    Data compiled from NHTSA recalls, manufacturer TSBs, automotive forums, and AI-assisted research. No aggregated owner-report counts available for this vehicle yet.