2007 Pontiac G6 powertrain problems

The transmission shift cable, which connects the gear shifter to the transmission, fractures or breaks. When this happens, the gear selection shown on the shifter does not match what the transmission actually does. The vehicle may not stay in the selected gear, or may roll away when parked in Park. In some cases, the cable fails again after a recall repair was performed.

When: Failures reported from 34,000 miles through 160,000+ miles. Some occurred less than 2 years after recall repair (which was intended to fix this issue).

Symptoms owners cite: Shifter moves freely without engaging gears; Car does not stay in Park when shifter is moved to Park position; Vehicle rolls away or backward after being placed in Park; Unable to shift out of Park; Transmission gear selection does not match what shifter indicates; Car stuck in Drive or Reverse; Cannot start vehicle when shift cable fails (stuck in Drive prevents engine start)

Repairs/costs cited: Recall 14152 (NHTSA Campaign 14V224000) issued to replace transmission shift cable kit (part # 23238001). However, owners report the recall repair failed in multiple cases within 1–2 years. Dealers initially refused to replace under warranty because recall repair window had passed (only 1 year warranty on recall work). Replacement cable costs cited by owners as $400–complete cable replacement required.

Recalls/TSBs owners mention: Recall 14152 (NHTSA Campaign 14V224000) issued for 2005–2008 model years manufactured May 26, 2004 to September 28, 2007. Recall stated: 'If the transmission shift cable fractures while the vehicle is being driven, the transmission gear selection may not match the indicated gear and the vehicle may move in an unintended or unexpected direction, increasing the risk of a crash. Furthermore, when the driver goes to stop and park the vehicle, despite selecting the Park position, the transmission may not be in Park. If the vehicle is not in the Park position there is a risk the vehicle will roll away.' However, some owners with vehicles in the affected model-year range report their VINs were not included in the recall list, despite experiencing the exact failure described. Some owners report recall parts were unavailable for months/years after recall notification. Some owners report the recall repair itself failed and dealers refused to repair again because 1-year warranty on recall work had expired.

When accelerating from a stop, the transmission hesitates to engage, remains in what feels like Neutral, or takes several seconds to move. When it finally engages, it does so abruptly with a hard shift or jerk that throws occupants back. Intermittent and difficult to replicate at dealer.

When: Reported at 42,000 miles; some owners note it started 2+ years before complaint. Happens randomly—sometimes multiple times daily, sometimes weeks between episodes.

Symptoms owners cite: High engine revs with no transmission engagement for 1–5+ seconds after pressing gas; Occupants thrown back in seats when transmission finally engages; Hard shift or jerking sensation during gear changes; Car does not move or moves very slowly when trying to leave from a stop; Happens intermittently at any temperature or driving condition; Traction control engages when failure occurs on wet/icy roads, wheels spin; On highway, sudden downshift and loss of power mid-drive

Repairs/costs cited: Owners report dealer inability to replicate failure during diagnostic visits, so no repairs performed. One owner cited estimate of $4,000 for new transmission. Some owners report attempting fuel system cleaning without resolution. Part of transmission may involve 3,5,R clutch wave plate failure (identified per GM Service Bulletin 09-07-30-012), though repair costs were described as 'phenomenal' and GM refused to cover beyond 100,000 miles.

Recalls/TSBs owners mention: No recall issued for this failure mode. Dealers have stated they cannot help unless they can replicate the problem. GM customer relations have denied the condition exists or refused to discuss with vehicle engineers because it could not be duplicated during dealer diagnostics. Clutch wave plate issue identified in Service Bulletin 09-07-30-012 but not covered under warranty once vehicle exceeds 100,000 miles.

The Body Control Module, which controls brake lights, transmission solenoid signals, cruise control, power locks, and other vehicle systems, fails or malfunctions. This causes multiple secondary failures: brake lights illuminate when brakes are not applied or do not illuminate when they should, cruise control disengages unexpectedly, shifter problems, and transmission solenoid issues.

When: Reported at mileages ranging from 1,400 to 159,000 miles. Some failures occurred after recall service (Campaign 14V252000) intended to fix these issues.

Symptoms owners cite: Brake lights illuminate continuously or when brakes are not applied; Brake lights do not illuminate when brake pedal is depressed; Brake warning indicator remains illuminated on instrument panel; Cruise control turns off or fails to activate; Cruise control does not deactivate when brake pedal is pressed; Shifter engages into gears independently without driver input; Difficulty shifting out of Park; Power door locks fail to lock or unlock properly; Transmission solenoid becomes defective

Codes mentioned: Body Control Module failure code (diagnostic required to identify)

Repairs/costs cited: BCM replacement required. One owner reported repair did not resolve the failure. Owners cite difficulty getting dealer appointments; some waited weeks due to dealer staffing issues. Independent mechanics have performed diagnostics showing BCM failure.

Recalls/TSBs owners mention: NHTSA Campaign 14V252000 issued for electrical system, electronic stability control, exterior lighting, service brakes (hydraulic), and vehicle speed control. However, some owners report the repair under this campaign did not correct the failure, or parts were unavailable for extended periods. Some owners reported experiencing the same failures after the recall repair was completed.

Transmission solenoid, which controls gear shifting via electrical signals from the BCM, becomes defective. Results in inability to shift gears or erratic shifting behavior.

When: Reported at 80,000 miles in at least one case.

Symptoms owners cite: Gears fail to shift; Difficult or impossible to shift gears; Transmission behaves as if in Neutral even when shifted into Drive; Gear slipping or intermittent slipping from gearbox

Repairs/costs cited: Solenoid replacement required. One owner reported independent mechanic diagnosed this as caused by electrical issues from BCM failure.

Camshaft position sensor or camshaft actuator solenoid sensor fails, causing check engine light and transmission problems.

When: Reported at 110,000 miles in one case.

Symptoms owners cite: Check engine light illuminates; Vehicle fails to shift gears when accelerating; Vehicle jerks severely when gear shifter is placed in any position

Repairs/costs cited: Both camshaft position sensor and camshaft actuator solenoid sensor replaced in one case, but failure recurred.

Engine stalls while driving or will not restart after being shut off. Check engine light may illuminate. In one case, transmission shift cable failure prevented restart (vehicle locked in Drive).

When: Various mileages reported, including at 80,000 miles.

Symptoms owners cite: Engine stalls while driving at 20–35 mph; Vehicle unable to be restarted; Check engine light illuminates before or during stall; Engine shut-off unexpectedly

Repairs/costs cited: One case involved shift cable failure preventing restart; another involved battery, rotor, and brake shoe replacement without resolving the issue; one case involved fuel system cleaning without resolution.

When cruise control is engaged while driving uphill and wipers are running on pulse/intermittent setting, the wipers stop functioning at the moment the transmission is attempting to downshift, obscuring all windshield vision. The failure is reproducible under specific conditions (cruise control + hill/incline + wiper pulse mode).

When: Reported at 50 mph on highway with mountains/hills, and at 35 mph on typical hills in other regions.

Symptoms owners cite: Windshield wipers stop functioning momentarily during transmission downshift on cruise control; Complete loss of windshield vision during wiper stoppage; Failure reproducible in different locations with similar terrain

Repairs/costs cited: Dealer suggested workaround: use constant wiper setting instead of pulse. Dealer could not replicate during city testing. No parts replacement mentioned.

Recalls/TSBs owners mention: GM customer relations stated the condition 'did not exist' because it could not be replicated during dealer testing. GM refused to discuss the issue with vehicle design or engineering staff. This was experienced by owner in multiple states with reproducible conditions, but GM dismissed the complaint.

Catalytic converter fails, triggering check engine light. Owner at 80,000 miles on a 2007 G6 with 3.5L engine had converter failure, but GM's emissions warranty extension to 100,000 miles only applies to 2.3L engines, not 3.5L.

When: At 80,000 miles (just past typical bumper-to-bumper warranty; GM extended emissions coverage to 100k for 2.3L but not 3.5L).

Symptoms owners cite: Check engine light illuminates; Emissions test fails

Repairs/costs cited: Owner's independent mechanic performed diagnosis and filed report; GM refused to accept independent mechanic's diagnostic report for goodwill warranty claim. Repair cost paid out of pocket by owner.

Recalls/TSBs owners mention: GM stated they only process goodwill/warranty claims through authorized GM dealers, not independent mechanics. Refused to honor the 80,000-mile failure under any extended coverage, and dealerships were unable to provide appointment for weeks. Recall Campaign 14V224000 involves powertrain but did not cover this specific emissions component failure.

Check engine light and traction control warning light illuminate. Vehicle exhibits jerky feeling during driving. Diagnostic inspection revealed no trouble codes despite lights being on.

When: Ongoing condition; reported at time of complaint.

Symptoms owners cite: Check engine light remains on; Traction control light blinks intermittently; Small jerky feel every time vehicle is driven; Vehicle stalls or nearly stalls during turning or acceleration

Repairs/costs cited: Full diagnostic inspection found no codes. Fuel system cleaning and brake fluid exchange performed without resolving traction control light issue.