P0174 on Chrysler: How to Diagnose & Fix
System Too Lean (Bank 2)
5 Chrysler models · 7 documented issues · 7 critical · $100-$8,500 repair
P0174 on Chrysler by model: symptoms, diagnosis and fix
PT Cruisers are extremely prone to overheating from multiple causes: radiator fan relay failure, fan motor failure, thermostat sticking closed, radiator clogging, and water pump failure. The high-speed fan relay is the most frequent single failure point. Overheating leads to head gasket failure. This is one of the most universally reported problems across all model years.
Common Symptoms
- Temperature gauge climbing above normal, especially at idle
- A/C compressor disengaging (safety cutoff from high temps)
- Radiator fan not running with engine hot
- Steam or coolant smell from engine bay
- Check engine light with coolant temp codes
How to Fix
Diagnose root cause systematically: check fan relay (5149541AA) first, then fan motor, thermostat (Stant 45359), water pump, and radiator. Replace radiator cap (frequently causes overpressure issues). Cooling fan module 5017407AB for complete fan assembly replacement.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Radiator CapCross-ref31518
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
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Sources for this issue (1)
Head gasket failure is common, especially on turbo models. The aluminum cylinder head is susceptible to pitting from acidic coolant which compromises the gasket seal. Turbo models experience higher cylinder pressures that accelerate failure. Overheating from cooling system issues frequently triggers head gasket failure.
Common Symptoms
- White smoke from exhaust (coolant entering combustion)
- Coolant loss with no visible external leak
- Engine overheating
- Milky residue on oil cap (coolant in oil)
- Bubbling in coolant overflow tank
How to Fix
Replace head gasket with Fel-Pro MLS gasket. HS 9946 PT for 2001, HS26206PT-1 for 2002-2009, or individual gasket 26206PT for 2002-2010. Machine cylinder head surface if pitting present. Replace thermostat and flush cooling system. Check head for warpage before reinstalling.
Sources for this issue (1)
The turbocharger on GT and turbo models fails from oil starvation, wastegate actuator failure, and bearing wear. Failures reported as early as 60,000-78,000 miles. Turbo failure is often followed by head gasket failure within months due to changes in combustion pressure dynamics.
Common Symptoms
- Loss of boost / reduced power
- Blue or white smoke from exhaust under acceleration
- Whining or grinding noise from turbo area
- Check engine light with boost pressure codes
- Oil leaking from turbo seals
How to Fix
Replace turbocharger assembly (Mopar 4884183AD) and turbo oil feed line (4891252AA). Must address root cause: oil feed line restriction, wastegate failure. Replace oil feed and drain lines during turbo replacement. Use only full synthetic oil and change every 3,000 miles. Idle 30-60 seconds before shutdown to cool turbo.
Sources for this issue (1)
The 2.4L Tigershark MultiAir II engine has defective piston rings that allow oil into the combustion chamber. Owners report consuming 1 quart of oil every 500-1,000 miles. Engine can seize without warning if oil drops too low. Class-action settlement (Wood, et al. v. FCA US, LLC) reached. FCA extended powertrain warranty to 7 years/100,000 miles under CSN W80.
Common Symptoms
- Oil consumption of 1+ quart per 1,000 miles
- Low oil pressure warning light
- Blue smoke from exhaust
- Engine stalling or seizing without warning
- Rough idle or misfires
How to Fix
Contact FCA dealer for oil consumption test under CSN W80 warranty extension. If test fails, engine long block replacement under extended warranty (7 years/100,000 miles). PCM/TCM reprogramming may reduce consumption in some cases. File claim at fcatigersharksettlement.com if eligible. Use full synthetic 0W-20 oil.
Sources for this issue (1)
The 3.3L and 3.8L V6 engines suffer from water pump failures, thermostat failures, and radiator fan relay failures. The water pump weep hole is a common leak point. Overheating can cause head gasket failure. The cooling fan relay is a frequent failure point causing overheating at idle.
Common Symptoms
- Engine overheating, especially at idle or in traffic
- Coolant leak from water pump area
- Temperature gauge fluctuating
- Heater blowing cold air
- Radiator fan not running at idle
How to Fix
Replace water pump (Gates 43090 for 3.8L), thermostat (Stant 45359, 195F), and radiator cap as a set. Check cooling fan relay in fuse box. Flush entire cooling system with Mopar OAT coolant (68048953AB). Monitor temperature gauge regularly, especially in summer traffic.
Sources for this issue (1)
The 3.6L Pentastar V6 in Pacifica models suffers from engine stalling due to loose ground connections (recall NHTSA 19V348), crankshaft position sensor sync issues, and premature head gasket failures typically around 75,000-85,000 miles. Cooling system failures can lead to coolant entering the combustion chamber, requiring complete engine replacement.
Common Symptoms
- Engine stalls without warning while driving
- Loss of power steering assist during stall
- Coolant level dropping without visible external leak
- White smoke from exhaust
- Engine overheating
How to Fix
Check recall NHTSA 19V348 for ground connection fix. For head gasket, use Felpro head gasket set HS26517PT. Monitor coolant level frequently - dropping level with no visible leak is a red flag. If coolant enters oil system, engine replacement may be required ($5,000-$8,000). 2020+ models reportedly have improved head gasket design.
Sources for this issue (1)
P0174 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0174 mean on a Chrysler?
P0174 stands for "System Too Lean (Bank 2)." P0174 means the engine computer detected that the air-fuel mixture on Bank 2 (the side of the engine with cylinder 2) is running too lean — too much air relative to fuel. The computer monitors this through the oxygen/air-fuel sensors and fuel trims; when it has to add a large amount of extra fuel to compensate and still can't reach the target, it flags the mixture as too lean. A lean condition can cause rough idle, hesitation, or misfires, and over time can raise combustion temperatures. Because it's Bank 2 specific, an unmetered air leak on that bank or a fuel delivery shortfall is typical. On Chrysler it is documented across 5 models: PT Cruiser, 200, Town & Country, Pacifica, Sebring.
What are the most common causes of P0174?
The most common causes of P0174 are: Vacuum or intake air leak (hoses, gaskets, PCV), Dirty or failing mass airflow (MAF) sensor, Weak fuel pump or restricted fuel filter (low fuel pressure), Clogged or underperforming fuel injectors, Leaking intake manifold or throttle body gasket, Faulty or contaminated oxygen / air-fuel sensor, Exhaust leak upstream of the oxygen sensor, Stuck-open EGR valve. The specific cause varies by vehicle.
How much does it cost to fix P0174 on a Chrysler?
Published repair estimates on Chrysler range from $100 to $8,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0174 on a different make?
View P0174 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.