Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2008 Chevrolet Cobalt owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2008 Chevrolet Cobalt. The contact stated that while driving approximately 30-35 MPH, the power steering warning light illuminated before the vehicle lost power. The contact shifted the vehicle into park and restarted the vehicle and the vehicle regained normal functionality. The failure occurred a total of 4 times. The contact had not taken the vehicle to the dealer. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 114,000.
Tl* the contact owns a 2008 Chevrolet Cobalt. While driving 30 MPH, the contact was informed that the vehicle was on fire. The contact stated that the fire was confined to the engine compartment. The contact noticed an abnormal fuel odor in the vehicle. The fire department extinguished the fire. A fire report was not filed. The vehicle was towed to an independent mechanic and then to the contact's residence. The vehicle was not repaired. The vehicle was not included in NHTSA campaign number: 12V459000 (fuel system, gasoline). The manufacturer was not made aware of the issue. The approximate failure mileage was 119,000.
Was driving to san diego, first stop of several on a vacation. Stopped at a stop light. Went to proceed as light turned green, heard a scraping and grinding sound; there was little to no power for the car. It couldn't go above 30 MPH, and made a "loud noise" (as stated on paperwork from dealership). Got to city (by the bay) Chevrolet. I ended up spending $1334.21 for a new catalytic converter and two gaskets. I was also out $111.26 for a rental as I was going to disneyland and knott's berry farm after a stop to san diego. I had to have the rental from Thursday to Saturday or I would have missed time at disneyland. I picked the day for knott's berry farm. …
Engine light came on.... Had it checked by Firestone... They told me the 2nd cylinder was misfiring per the diagnostic code.. Should be 130 psi and only registering 90 psi....then while stopped longer than 30 seconds "service traction" light comes on.....asking $2300 to repair.... Why would one of the four cylinders go bad.....complained to GM and they told me I needed a certified GM dealer to look at it so I took it to GM also for diagnostic and they are saying misfire in 2nd cylinder which is what the diagnostic code says- per the paperwork given me they are not sure what the repair is going to entail or how to fix the problem..... Per internet complaints this s a problem that has occurred many times in cobalts.... Is it because no one got hurt or died that they don't want to consider this a recall? …
I started my car in my driveway, it started and then stalled immediately and would not start at all. I diagnosed it along with my friend who is a certified mechanic. The cam chain guides broke at less than 79000 miles, causing slack in the cam chain which caused it to jump teeth on the intake cam, throwing it out of synchronization. This caused the intake valves to be open when the piston reached the top of its travel, which bent the valves. This is a very common issue on the 2.2 engines, but very unusual for such a low mileage vehicle. The engine has a 100,000 mile warranty but only for 5 years. I only drive on average 10,000 miles a year. The engine is well below 100,000 miles and GM will not admit that they have a design flaw on these engines and will not make this repair for me under warranty.
Coolant is not reading, air conditioner don't work and check engine light comes on. It will stay like this for a day or so then by the time I get it into the shop it starts to read again and the check engine light goes out air conditioner will work again and there are no codes to read. Repair shop can't find anything wrong. They said possible thermostat issue or sensor issue but without codes or check engine light on they have no idea. It keeps doing it but it seems to correct it self before I can get it back to the garage usually over a weekend when they are closed or very busy. I have had this issue for a couple months now, it has not appeared to cause any over heating or made any other sounds that I am aware of.
Tl* the contact owns a 2008 Chevrolet Cobalt. The contact stated that while driving at unknown speeds, for twenty minutes gas was leaking out of the tank and the fuel meter decreased to empty. However, there were no visual sign of fuel on the ground. Additionally, there was an abnormal odor of gas emerging in and out of the vehicle. The service tire pressure monitor light was illuminated. The vehicle was taken to an independent mechanic who informed the to contact the local dealer as well as the vehicle was not safe to drive. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was 55,875.
I had recalls fixed in 2015. And then suddenly power steering turns on and off. Never before they touched it was there an issue. It happens here and there and stops. This year is happening every day and won't go away. My power steering turns off in middle of driving. Dash board lights go off and car starts cranking. Goes super slow . I'm scared ita going to explode. I can't drive on freeway . And now besides the lock on screen coming on my engine light stays on now . Not sure what to do with it. Car shops can't help. When I 1st had the issue I called the dealer because they fixed the recall and they said nothing could be done because they had already fixed the recall
Start of the problem the gauges will go eratic, my car chimes a few dings then theft light comes on. I don't have a theft system. Ls model. Also effects the transmission(automatic) cause it will shift hard and jerk the car. The ac also shuts off during this issue, it will blow air but it won't be cold. Seems like the issue always comes back when it's extremely hot outside. This is an on going issue for about 5 years and it comes and goes. Every mechanic I went to their car reader can't read my car. Also it has happened while I was driving and again when I'm parked and just started the car. And I have had all the recalls fixed that were reported.
While driving on the route 20 at about 50mph it started to rain and all of a sudden my car "reduced engine power" light went on. My car started slowing down and I had to turn to the closest street so that I wasn't hit by the car behind me. This has happened before, last year while on the highway driving to cleveland, my car began rapidly slowing down and I couldn't pick up speed while pressing the gas. I took the nearest exit and had to wait two hours before the engine light would turn off. Also, while the check engine light is on, it also says "traction off" and my car shakes. Both times it was raining, and I was driving at 50mpr speeds.
Engine complaints in other Cobalt years
Frequently asked questions
How common are engine problems on the 2008 Chevrolet Cobalt?
NHTSA has 51 complaints about the engine & cooling of the 2008 Chevrolet Cobalt, 5% of the model year's 940 complaints. The component named most often is engine (2 mentions).
Is there a recall for 2008 Chevrolet Cobalt engine problems?
No. NHTSA lists no engine & cooling recall for the 2008 Chevrolet Cobalt, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2008 Chevrolet Cobalt engine problems start?
Half of the complaints with a recorded mileage happened before about 69,000 miles, and 12% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 4 fires and 2 injuries and 1 death to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.