2008-2013 Infiniti G37 Problems: 23 Known Issues

The VQ37VHR uses Variable Valve Event and Lift, a mechanical system on the intake side that varies lift continuously through an actuator motor driving a control shaft, managed by its own control module. When the actuator motor, the control shaft position sensor, or the VVEL module fails, the engine drops into a severe limp mode with essentially no throttle response — the car becomes undrivable rather than merely down on power. Owners typically see a scatter of seemingly unrelated codes alongside the failure, which sends diagnosis in the wrong direction. Contributing factors include oil starvation and sludge in the VVEL assembly from extended oil change intervals, and moisture or connector corrosion at the module.

The crankshaft position sensor mounted on the transmission bell housing of the VQ37VHR is a documented failure point on G37s past about 80k miles. It typically fails when hot: the engine stalls after warm-up or extended driving, cranks without starting until it cools, then restarts normally. P0335 is stored. Owners who fit cheap aftermarket sensors report repeat failures, so the community advice is OEM or Hitachi only.

The VQ37VHR runs three timing chains — a primary and two secondaries — with plastic guides and hydraulic tensioners. The chains stretch and the guides wear, and because the tensioners rely on oil pressure to take up slack, any oil pressure loss or extended change interval accelerates it sharply. The first symptom is a rattle from the front of the engine on cold start that lasts a second or two until pressure builds, progressing to a rattle that persists at idle. Left alone, stretch pushes cam timing out of correlation and sets timing codes; in the worst outcome the chain skips or a guide fragments, and on this interference engine that means bent valves.

On pre-2012 VQ37VHR engines the oil gallery gaskets (the T- and L-shaped gaskets that seal the timing chain cover to the block) crack and fail, and unlike an ordinary external oil leak this one matters mechanically: the internal leak path bleeds down oil pressure feeding the top end. Low oil pressure on this engine starves the VVEL assembly and the cam and rod bearings, and owners who dismiss the warning have lost engines to it. There is often no early sign; what owners see is a low oil pressure warning or gauge reading that comes up at idle when hot, limp mode, and valve timing codes such as P0011 and P0021. Oil in the spark plug wells or on the exhaust manifolds points to a separate cam cover gasket leak, not this failure.

The VQ37VHR engine develops a failure of the oil gallery gaskets that seal the oil passages between the front timing chain cover and the block. When a gasket fails, oil pressure drops, often without warning, which can bring on limp mode and P0011/P0021 cam timing codes and, if driven, severe internal damage.

The Hitachi coil-on-plug units on the VQ37VHR are a recurring failure item on higher-mileage G37s. Heat and electrical stress cause the coil body to blister or bulge, producing a random or single-cylinder misfire, rough idle and flashing check-engine light. Infiniti bulletin ITB11-017A, written for the FX35 (not the G37), ties P0300-P0306 misfires and blistered coils to poor engine grounds and battery cables, and owners and parts guides apply the same logic to the G37. On the G37 the coils are reached by removing the engine cover, airbox, intake tube and moving the throttle body aside; the middle coil on each bank is the hardest to get to.

Early-production VQ37VHR engines consume noticeably more oil than owners expect, and the 2008-2010 build years are the most affected. The consumption is real rather than imagined leakage, driven by ring and cylinder wear characteristics on early blocks, and it is aggravated by hard driving and by the long factory oil change interval. The practical danger is not the oil itself but what running low does to the rest of the engine: the VVEL assembly and the timing chain tensioners are oil-pressure dependent, so an owner who tops up only when the light comes on is quietly setting up a far more expensive failure.

Manual transmission G37s suffer from premature concentric slave cylinder (CSC) failure. The internal seal degrades, causing clutch fluid to leak into the bell housing and resulting in a soft or sinking clutch pedal.

The FS6R31A 6-speed manual fitted to G37 Sport/6MT cars develops synchro grind, most often on 2nd, 5th and 6th (some report 3rd) during quick upshifts or when skipping gears. It is usually masked when shifting gently and shows up under spirited driving. Early in the car's life Infiniti replaced complete gearboxes under warranty—some owners report two or three replacements—while other dealers denied a known problem. The same brass synchro weakness is shared with the 370Z.

The 7-speed automatic introduced for the 2009 G37 developed a widely reported drivability complaint: a hard clunk on the 2nd-to-1st downshift when coasting to a stop, gear hunting/searching under light throttle, delayed or harsh upshifts when cold, and in some cases stored incorrect-gear-ratio codes. The MyG37 '7-speed transmission reprogram' thread runs well past 170 pages of owner reports. Infiniti responded with a series of TCM/ECM reprogramming bulletins (owners cite ITB10-075 and later ITB12-027 revisions) rather than hardware replacement; only a minority of cars needed a torque converter or valve body.

A varistor inside the Occupant Classification System control unit in the front passenger seat cushion was manufactured out of specification and can interrupt the signal between the OCS and the airbag control unit. When that signal is lost the airbag control unit suppresses the passenger frontal airbag, so it will not deploy in a crash even with an adult properly belted in the seat. NHTSA campaign 08V521000 covers the 2008 G37 Coupe together with 2007-2008 G35 sedans, EX35, and several Nissan models, totaling 204,361 vehicles. The recall began November 4, 2008.

A programming error left the power window switch controller with an auto-reverse activation threshold higher than Nissan's specification. The window must encounter more resistance than intended before it reverses, so a hand, arm, or a child's neck caught in a closing window is subjected to considerably more clamping force before the anti-pinch function releases. NHTSA campaign 11V538000 covers 2011 and 2012 G37 Coupe vehicles and 2011 Nissan 370Z built July 2, 2011 through August 29, 2011. The recall began December 5, 2011.

Like the G35, the G37 suffers from electronic steering wheel lock actuator failures that prevent the vehicle from starting. The internal motor in the lock mechanism burns out or the control module loses communication with the BCM.

The hydraulic power steering circuit on the G37 develops leaks at the high-pressure hose, its crimped hard-line sections and the reservoir-side return hose as the rubber ages. Owners describe fluid coating the underside of the car, a whine from the pump when low, and difficulty pinpointing the source; some report repeated hose failures. Because the pressure line routes close to the exhaust and engine, heat accelerates the degradation.

The dashboard topper material degrades under sustained sun and heat, first going soft and tacky, then developing shiny patches, cracks, and chipping — usually starting at the defroster vents and the instrument binnacle. The degraded surface turns reflective and throws glare onto the windshield severe enough to interfere with forward vision in low sun, which makes this a visibility problem rather than a purely cosmetic one. The defect is documented across 2008-2009 G37 alongside 2006-2008 G35 and M35 and was the subject of class-action litigation against Nissan. Nissan extended warranty coverage for melting dashboards on certain other vehicles but did not extend it to these models.

Separate from the melting dashboard, the painted/soft-touch coating on the steering wheel spokes and rim of 2008-2009 G37s (and 2007-2008 G35 sedans sharing the wheel) peels and chips, often before 50k miles. A 25-plus-page G35Driver thread and multiple MyG37 threads document owners getting the wheel replaced under warranty; Infiniti issued a bulletin acknowledging the defect but many cars were already out of warranty by then, and some dealers offered a repaint instead of replacement.

Water entering the sunroof tray is meant to drain through four tubes routed down the A- and C-pillars. Debris blocks the drain nipples at the tray corners, the tray overflows, and water runs into the headliner and down the pillars into the cabin. Owners report soaked footwell carpet, water dripping from the headliner or map light, and a persistent musty smell. Because the water follows the pillars past wiring and body modules, it commonly surfaces as electrical faults first, and a car with unexplained module behavior and damp carpet is almost always leaking here rather than suffering an independent electrical failure. This is the leading cause of interior water intrusion on the chassis.

The 2009-2013 G37 Convertible's retractable hardtop depends on a trunk-mounted hydraulic pump, multiple cylinders, and a trunk 'separator' (tonneau divider) that must be latched before the top will cycle. Common failures reported across the multi-part 'Convertible Top Issues' threads on MyG37 are a 'check separator' message from a misaligned or broken separator latch, a hydraulic pump that fails or whose rubber isolator bumpers deteriorate, and roof-in-operation faults that stop the top mid-cycle and force manual closing. Dealer quotes for a complete hydraulic system run into the thousands.

Front hub bearings on the G37 (sedan, coupe and especially the heavier AWD G37x) fail well before most owners expect, typically between 50k and 90k miles. The symptom is a hum or drone above roughly 45-50 mph that changes pitch when the car is loaded in one direction (louder turning one way, quieter the other) and can be felt as vibration through the steering wheel. Owners report repeat failures and both sides eventually going.

Early G37s develop coolant leaks from the upper radiator hose assembly and its plastic bleeder/connector fittings, which embrittle with age and heat and can split suddenly. Owners report sudden coolant loss and overheating warnings, dried coolant residue around the thermostat housing, and repeat leaks after a hose is replaced because the multi-piece OEM hose assembly has several joints. The plastic bleed port is repeatedly named as the weak point.

G37 fuel gauges commonly read wrong as the cars age: the needle sticks at half or full, drops suddenly, or the low-fuel light comes on with fuel remaining. The saddle-style tank uses a main and sub level sensor; wear on the float-arm resistor track in either sender produces erratic readings. Because the fuel data passes through the body/AC control electronics before the cluster, owners have chased wiring and even module faults after replacing a sender. There is no known TSB, but the fault is well documented across MyG37 and G35Driver.

Owners across model years report the G37's air conditioning gradually blowing warm as refrigerant escapes, most often from the compressor shaft seal, the high-pressure service fitting or cutoff-switch O-rings, and occasionally the condenser. The system holds only about 1.1 lb of R-134a, so a small leak empties it quickly and the compressor clutch stops engaging on low pressure. CarComplaints lists 'A/C blowing warm air' among the top 2013 G37 problems at roughly $2,800 average repair cost.

On Bose-equipped G37s the trunk-mounted amplifier is the most common audio failure. Sound cuts out entirely or intermittently with no error on screen—the head unit, navigation and controls keep working, but nothing comes from the speakers. Owner diagnosis on G35Driver and MyG37 starts with the BOSE AMP fuse and the head-unit self-diagnostic, which shows the amp not communicating; internal solder-joint failure is the usual root cause.