This service bulletin provides information on the cold start control system in DI engines to reduce cold start emissions and improve fuel economy.
full bulletin at NHTSA ↗2008 Chevrolet Cobalt fuel system problems
moderate 43 complaints filed with NHTSA · avg repair $1,200 · see fuel system across all vehicles →
Failure mileage
Complaints
43
Recalls
0
Avg fix
$1,200
1crash
1injury
What stands out
Owners have filed 43 fuel system 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 6 model years of Chevrolet Cobalt in our records for fuel system problems, this one ranks #3 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering fuel system 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 service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
full bulletin at NHTSA ↗This bulletin provides information on the TOP TIER Detergent Gasoline Licensed Brands and the TOP TIER Diesel Fuel Licensed Brands that are recommended for use in all GM vehicles and the TOP TIER FUELS website URL.
full bulletin at NHTSA ↗This service bulletin provides the technician with additional information on fuels, fuel additives and fuel management.
full bulletin at NHTSA ↗This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners consistently describe fuel odors ranging from faint to overpowering, detected both inside the cabin and externally. The root issues center on fuel system leaks at the pump module and fuel lines. The most commonly cited failure is a cracked plastic port on the fuel pump's modular reservoir or a crack in the fuel pump housing itself, causing fuel to leak from the top of the tank or onto the protective shield underneath the vehicle. Fuel line corrosion also appears, especially in designs where lines sit in a pocket above the muffler, trapping heat and moisture. Mechanics have found cracked fuel return lines, damaged fuel supply lines, and corrosion at fuel line connections.
Fuel leaks typically occur between 30,000 and 200,000 miles, though some are reported as early as 2,700 miles. Owners report fuel pooling underneath the vehicle, sometimes near the exhaust system—a fire hazard concern mentioned repeatedly. Some vehicles also exhibit difficulty starting, check engine lights, and stalling. Fuel economy has degraded in several cases.
A frustration running through the narratives is coverage gaps: owners note that 2006–2007 Cobalts were recalled under campaign 09V419000 and 12V459000, yet many 2008 models with identical symptoms were not included despite having the same components and failure modes. Repairs performed outside recalls have cost owners $200 to $750 per incident, with some corrosion issues recurring within two years.
Same Chevrolet Cobalt fuel system reports on nearby years: 2005 · 2006 · 2007 · 2009 · 2010
Failure modes owners describe
Cracked fuel pump housing/module
The plastic supply port or housing of the fuel pump modular reservoir cracks, allowing fuel to leak from the top of the fuel tank or pump assembly onto the protective shield below the vehicle.
When: 30,000 to 200,000 miles; one reported at 2,731 miles
Symptoms owners cite: Strong fuel odor inside and outside the vehicle; Fuel leaking from underneath the vehicle; Fuel pooling on protective shield under tank
Codes mentioned: P2270
Repairs/costs cited: Fuel pump module or pump assembly replacement; costs reported at $200 to $750; one case cited module kit cost of $745.12
Recalls/TSBs owners mention: NHTSA Campaign 12V459000 (fuel pump), NHTSA Campaign 09V419000 (2006–2007 model coverage); many 2008 VINs excluded from recalls despite identical symptoms; some dealers denied coverage citing flood damage history or mileage over 120,000; Louisiana-registered vehicles initially excluded from campaign coverage
Cracked fuel lines and return lines
Fuel supply lines, return lines, or fuel line assemblies crack and leak fuel. Some lines show corrosion due to design placement in a pocket above the muffler, trapping heat and moisture.
When: 32,000 to 175,000 miles; corrosion recurring after 2 years in one case
Symptoms owners cite: Fuel odor while driving and when parked; Visible fuel leaking from rear driver-side wheel well or underneath vehicle; Fuel leaking onto the exhaust system; Degraded fuel economy; Difficulty starting
Repairs/costs cited: Fuel line replacement; one case replaced entire fuel line and fuel pump assembly as one unit; costs cited at $200 to $750; corrosion issues requiring replacement again after 2 years
Recalls/TSBs owners mention: NHTSA Campaign 12V459000; most lines not covered by recall; one GM representative confirmed design flaw (muffler placement causing heat/moisture trap) but declined responsibility; dealer refused to honor warranty due to flood damage history
Fuel pump connector burn/ignition risk
Fuel pump electrical connectors overheat and burn, creating a fire hazard during vehicle operation.
When: Unspecified mileage; associated with difficulty starting
Symptoms owners cite: Difficulty starting the vehicle; Burned fuel pump connectors visible to mechanic; Risk of ignition during driving
Repairs/costs cited: Connector repair or replacement (not detailed); multiple owners expressed fear of fire but repair status not clearly stated in narratives
Recalls/TSBs owners mention: GM issued recalls for 2007–2009 Cobalts with this problem; 2008 model owner's vehicle was excluded from recall despite identical failure
Fuel delivery system malfunction with check engine light
Fuel system fails to deliver fuel properly, accompanied by engine warning lights and intermittent stalling.
When: 2,731 miles (very early failure); at least one case at 187,000 miles
Symptoms owners cite: Check engine warning light illuminated; Abnormal fuel odor while driving; Vehicle stalling at various speeds; Difficulty starting after short parking periods
Codes mentioned: P2270
Repairs/costs cited: Root cause not determined in one early case; fuel pump assembly leaking in another case
Recalls/TSBs owners mention: Dealer and manufacturer notified in some cases; no assistance provided in narratives reviewed
Synthesized from 43 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Had fuel system trouble with your 2008 Chevrolet Cobalt?
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 fuel system problem on the 2008 Chevrolet Cobalt?
It's a documented issue but not catastrophic. 43 complaints have been filed. Repairs average $1,200 and most owners catch it before it causes a breakdown.
At what mileage does the fuel system typically fail?
Across the 37 complaints that reported odometer mileage, most fuel system failures cluster between 56,000 and 120,000 miles, with the median around 92,071. A quarter of owners report trouble before 56,000; a quarter make it past 120,000. 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 $1,200 for fuel system 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 fuel system?
No active recalls currently cover fuel system 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/2008/Chevrolet/Cobalt.
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.