This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
full bulletin at NHTSA ↗2007 Pontiac G6 engine problems
severe 28 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
28
Recalls
0
Avg fix
$3,100
1crash
1fire
1injury
What stands out
Owners have filed 28 engine complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Among the 5 model years of Pontiac G6 in our records for engine problems, this one ranks #2 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
full bulletin at NHTSA ↗This service bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
full bulletin at NHTSA ↗This service bulletin provides technicians with information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
full bulletin at NHTSA ↗This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners consistently cite coolant leaks as the dominant problem. Intake manifold and coolant crossover gaskets fail repeatedly even after radiator, overflow tank, and hoses are replaced—one owner spent six months making repairs himself after $8,000–$9,500 in cumulative costs. Water pump gaskets deteriorate when DEX-COOL antifreeze contacts the metal, and radiators crack repeatedly within months.
Engine stalling without warning is a secondary pattern. Multiple owners describe the engine shutting down at low speeds or stoplights, with power steering and brakes failing simultaneously. One stall at 30 mph resulted in a collision. Dealers cannot replicate the issue, leaving owners undiagnosed. Some compare the problem to GM's ignition-switch recall on other models.
Catalytic converter failures occur prematurely (around 135,000 miles despite replacements at lower mileage). Owners report GM recalls supposedly expire at 120,000 miles, but no recall notices were sent, and the manufacturer refuses to honor claims beyond that threshold. Fuel system safety concerns include a leaking fuel rail at 47,000 miles and gasoline smell through AC vents. One engine caught fire in the dealer's lot due to rodents nesting in the exhaust header. Reduced engine power limp mode triggered by throttle issues forces vehicles to 30 mph, creating highway hazards. Camshaft sensor codes persist even after replacement.
Same Pontiac G6 engine reports on nearby years: 2005 · 2008 · 2009
Failure modes owners describe
Intake manifold and coolant crossover gasket leaks
Coolant leaks from intake manifold gasket (upper corner, passenger side) and coolant crossover pipe gasket (driver side). Leaks persist or recur after initial repairs including radiator, overflow reservoir, hoses, and clamps replacement.
When: Around 160,000 miles; some occurrences noted at 70,000 and 140,000 miles
Symptoms owners cite: Coolant leaking from bottom corners of radiator initially, traced to gaskets; Orange/red liquid visible underneath vehicle; Vehicle parked due to constant leaks
Repairs/costs cited: Owners replaced overflow reservoir, 3/4 inch hose tee, clamps, transmission cooling lines, radiator, oil pressure switch, water pump gasket; costs cited $200+ per repair cycle
Engine stalling during deceleration and stop
Engine shuts off unexpectedly during deceleration, speed bumps, or when coming to a stop. Multiple instances over 2+ years; power steering and brakes fail when engine stalls. Owner notes similarity to ignition switch recalls on other GM models but G6 not included.
When: May 2013 through May 2015; timing unpredictable
Symptoms owners cite: Engine shuts off manually downshifting; Engine stalls after decelerating or over speed bumps; Engine stalls at stoplights; Power steering and brake loss when stalled; Difficulty restarting; key jiggling helps; Check engine light returns after service
Repairs/costs cited: Fuel system service, transmission cable adjustment ($203.25); issue persists after repair
Catalytic converter premature failure
Catalytic converter fails repeatedly despite prior replacements. P0420 code (catalyst system efficiency) reported multiple times. Owners claim GM recall exists at 120,000 miles but owners not notified and manufacturer refuses to honor after that threshold.
When: First replacement 2 days after purchase; failure again around 135,000 miles; recalls mentioned at 120,000 miles threshold
Symptoms owners cite: P0420 diagnostic code; Vehicle lacks power; Fails inspection due to catalytic converter and sensor codes
Codes mentioned: P0420
Repairs/costs cited: Catalytic converter replaced multiple times; costs not specified but owner notes parts repeatedly needed; GM states recall was at 120,000 miles
Recalls/TSBs owners mention: GM recall at 120,000 miles; manufacturer refuses to honor after threshold; requires NHTSA complaint for recall consideration
Reduced engine power and throttle response limp mode
Vehicle enters limp mode with 'reduced engine power' or 'service traction control' alert, limiting speed to ~30 mph. Occurs while driving at highway speeds (70 mph), creating safety hazard when pulling into traffic.
When: Timing unpredictable; occurs at various speeds including highway
Symptoms owners cite: Reduced engine power alert; Service traction control alert; Power drop from 70 mph to 30 mph max; Recurring episodes
Repairs/costs cited: Owner replaced gas pedal ($180) without resolution; scheduled throttle body replacement; repair costs unknown
Engine stalling without warning
Engine stalls unexpectedly while driving at various speeds. In one case, stall at 30 mph resulted in collision with another vehicle. Dealers unable to replicate failure for diagnosis.
When: At 31,437 miles and 98,000 miles; also 50,000 miles in one case
Symptoms owners cite: Engine stalls without warning while driving; Difficulty restarting after stall; Dealer cannot duplicate issue; Vehicle loses power and displays 'error' on instrument panel
Repairs/costs cited: No repairs completed; vehicles towed, not diagnosed
Engine compartment fire
Engine caught fire during dealership test drive. Insurance inspector attributed cause to rodent infestation with nest in exhaust header. Owner suspects design defect allowing animal access to area where engine heat ignites nesting material.
When: During service at dealership
Symptoms owners cite: Engine fire in compartment; Rodent nest in exhaust header
Repairs/costs cited: Insurance claim filed; cause identified as rodent infestation by inspector
Radiator cracking and coolant leaks
Radiator develops cracks causing coolant leaks. Multiple radiator replacements over short timeframes (Nov 2012, Feb 2013, May 2013) with aftermarket units, suggesting possible defect or incompatibility.
When: First crack noted Nov 2012; recurring through June 2013
Symptoms owners cite: Coolant leak from cracked radiator; Antifreeze/water loss
Repairs/costs cited: Radiator replaced three times in seven months with aftermarket units
DEX-COOL coolant reaction with water pump gasket
OEM water pump gasket deteriorates when in contact with DEX-COOL antifreeze, damaging gasket and surrounding metal. Causes antifreeze leak and water pump failure.
When: At 70,000 miles
Symptoms owners cite: Orange and red liquid on garage floor; Gasket deterioration and metal corrosion; Water pump leaking
Repairs/costs cited: Water pump replacement required
Recalls/TSBs owners mention: Manufacturer notified; no assistance offered
Fuel rail leak
Fuel rail develops leak, described as very unusual failure. Owner notes safety concern given hot engine compartment and fuel smell inside vehicle.
When: At 47,000 miles
Symptoms owners cite: Fuel smell inside vehicle; Fuel leaking from rail
Repairs/costs cited: Fuel rail repair/replacement; $500 in repairs; out of warranty
Exhaust system whistle and performance loss
Malfunction in exhaust system behind catalytic converters causes loud whistle at 2-3K RPM, reduction in performance and fuel economy. Owner reports this as known issue on internet for this model/engine combo.
When: Beginning at approximately 50,000 miles
Symptoms owners cite: Loud whistle at 2-3K RPM; Reduced performance; Reduced fuel efficiency
Repairs/costs cited: Complete exhaust assembly replacement from flex pipe back; $1,500 cost; GM dealer and Pontiac will not address
Recalls/TSBs owners mention: GM dealer and Pontiac refuse to address or repair
Camshaft sensor malfunction and engine hesitation
Engine hesitates and jumps when putting car in drive and during first and second gear. P0010 or similar camshaft sensor code triggers. Replacement of camshaft sensors does not resolve issue; problem recurs after vehicle sits then is restarted.
When: Recurring; resets after 2+ days of sitting
Symptoms owners cite: Engine jumping when shifting into drive; Engine jumping during first and second gear; Check engine light on; Camshaft sensor malfunction code; Problem recurs 10 minutes into drive after reset
Codes mentioned: Camshaft sensor malfunction
Repairs/costs cited: Camshaft sensors replaced; oil change and engine flush performed; issue persists
Toxic fumes from air conditioning system
After AC repair, toxic fumes come through vents when AC activated. Fumes are odorless but burn throat and eyes, presenting health hazard. Dealer claims nothing is wrong and fumes will eventually dissipate.
When: After AC repair at dealership; early in ownership (481 miles failure, 2,200 miles current)
Symptoms owners cite: Toxic fumes from AC vents; Throat burning; Eye burning; Odorless but hazardous fumes
Repairs/costs cited: AC repaired at Pontiac dealer; no resolution of fume issue
Recalls/TSBs owners mention: Dealer states nothing wrong with vehicle; fumes will go away on their own
Fuel smell through AC vents
Potent gasoline smell coming through AC vents, described as hazardous to health and potential fire hazard. Owner notes this is common issue in 2007 Pontiac G5/G6.
When: Timing not specified
Symptoms owners cite: Strong gasoline smell through AC vents; Health hazard from fume inhalation; Fire hazard potential
Oil leaks from crankshaft and oil pan gaskets
Oil leaks from front crankshaft and oil pan areas. Gaskets required replacement.
When: First noted at 20,000 miles
Symptoms owners cite: Oil leak from front crankshaft area; Oil leak from oil pan area
Repairs/costs cited: Oil pan and front crankshaft gaskets replaced under warranty at dealership
Recalls/TSBs owners mention: Warranty repair completed by dealer
Coolant system crossover gasket and accessory drive leaks
Vehicle leaks oil, antifreeze, and water. Diagnosed as crossover pipe and accessory drive needing replacement.
When: At 160,000 miles
Symptoms owners cite: Oil leak; Antifreeze leak; Water leak
Repairs/costs cited: Crossover pipe and accessory drive replacement required
Recalls/TSBs owners mention: Manufacturer notified of failure
Serpentine belt idler pulley wear
Idler pulley requires replacement.
When: Timing not specified
Repairs/costs cited: Idler pulley replaced
Recalls/TSBs owners mention: Owner requested reimbursement
Synthesized from 28 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Had engine trouble with your 2007 Pontiac G6?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2007 Pontiac G6?
It's a meaningful issue. 28 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Across the 22 complaints that reported odometer mileage, most engine failures cluster between 45,000 and 98,000 miles, with the median around 65,000. A quarter of owners report trouble before 45,000; a quarter make it past 98,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2007/Pontiac/G6.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.