2003-2008 Infiniti G35 Problems: 10 Known Issues

On early-build cars the fuel hose connection at the outlet of the fuel pump, on top of the fuel tank, may not have been properly seated during assembly. The connection can work loose while driving or during a start attempt. If it separates while driving the engine stops from fuel starvation; in either case fuel discharges from the pump outlet inside the tank cavity, and with an external ignition source present that becomes a fire. NHTSA campaign 02V245000 covers the defect, with owner notification beginning October 7, 2002.

The rubber fuel filler hose that runs from the filler neck to the tank can crack with age and exposure, letting raw fuel escape during refueling. Because the leak occurs at the pump with the nozzle running, any ignition source nearby creates a fire risk. NHTSA campaign 05V555000 covers the defect across a group of Nissan and Infiniti passenger cars and SUVs; the Infiniti portion of the recall began March 13, 2006.

A varistor inside the Occupant Classification System control unit, which sits in the front passenger seat cushion, was manufactured out of specification. Under certain conditions it interrupts the signal between the OCS and the airbag control unit. The airbag control unit interprets the lost signal by suppressing the passenger frontal airbag, so it will not deploy in a crash even with an adult properly seated. NHTSA campaign 08V521000 covers 2007-2008 G35 sedans along with the 2008 G37 Coupe, EX35, and a group of Nissan models — 204,361 vehicles in total. The recall began November 4, 2008.

The wire harness linking the belt tension sensor to the occupant detection sensor control unit under the front passenger seat is subject to relative movement as the seat is adjusted and as occupants shift. Over time that movement wears and oxidizes the terminals, interrupting the signal. With the signal lost the system cannot confirm occupant status and the airbag may not deploy in a crash. NHTSA campaign 10V175000 covers 2005-2007 G35 sedans built March 29, 2004 through August 25, 2006 and G35 coupes built April 1, 2004 through May 30, 2007. The recall began July 12, 2010.

The circuit boards inside the crankshaft and camshaft position sensors were built with improper solder joints — flux residue left during manufacturing accelerated heat-stress deformation of the solder. As the joint degrades the sensor signal drops out, most often once the engine bay is hot. The result is a Service Engine Soon light, a no-start, reduced engine power, or the engine simply cutting out without warning while driving. NHTSA campaign 03V455000 (Infiniti recall R3021) covers the defect on 2003 G35s built January through June 2002. Owner notification began December 22, 2003.

Some G35 VQ35DE engines burn oil fast enough that the level drops noticeably between oil changes. Owner reports run from about 1 quart every 1,000-2,000 miles to, in the worst cases, a quart every 300-500 miles. A few owners report engines that knocked or seized after the oil ran low. Reports come from every year from 2003 to 2007, but the problem is most associated with the 2005-2006 manual-transmission G35s and the 2007 coupe. Those cars got the "Rev-Up" version of the VQ35DE, which Infiniti revised internally and gave a higher redline. Automatic 2005-2006 cars did not get that engine. Piston ring design is the most-cited cause, so oil gets past the rings into the combustion chamber. Worn valve stem seals are also blamed. Because the oil drops slowly between changes, a G35 that isn't checked between changes can run dangerously low.

The sunroof tray is designed to collect water and route it through four drain tubes running down the A- and C-pillars. Debris packs the drain nipples at the corners of the tray, the tray overflows, and water spills into the headliner and down the pillars into the cabin. Owners find soaked front or rear floor carpet, water dripping from the headliner or map light area, and a persistent musty smell. Because the water tracks down the pillars it reaches wiring and body modules, which is why this shows up as electrical symptoms — including door lock actuators cycling on their own — rather than as an obvious leak. It is the single most common source of interior water intrusion on this chassis.

The dashboard topper material breaks down under sustained sun and heat, going soft and tacky to the touch before developing shiny patches, cracks, and chipping — typically first around the defroster vents and the instrument binnacle. Beyond the cosmetic damage the degraded surface becomes reflective, throwing glare onto the windshield that can be severe enough to obscure the driver's forward view in low sun. The defect is well documented across 2006-2008 G35 and M35 and 2008-2009 G37 vehicles and was the subject of class-action litigation against Nissan. Notably, Nissan extended warranty coverage for melting dashboards on some vehicles but did not do so for these G35, M35, and G37 models, so most owners face this as an out-of-pocket repair.

Certain G35 Coupe headlamp assemblies do not meet the vertical gradient and headlamp photometric value requirements of Federal Motor Vehicle Safety Standard 108. In practice the beam cutoff is poorly defined and light output falls outside the required pattern, so the roadway is inadequately lit and oncoming drivers may be glared. NHTSA campaign 06V394000 covers the defect, with the recall expected to begin on or about April 16, 2007. The remedy is replacement of the headlamp assemblies, not an aim adjustment.

The power window regulators in the G35 are prone to failure, causing windows to fall into the door or operate slowly. The plastic guide clips and cable mechanism wear out, especially in hot climates.