Bazz518

Im new to the cobalt world I just purchased a 2009 yellow Cobalt SS After getting the car home and going to start it the next day it fired right up for a few seconds then started to die and was struggling to stay running then after about 30 seconds it runs just fine. Once its running there is not problem. It has a cold air intake, ZZP down pipe, and is ZZP tuned. Im thinking it may be a fuel pressure problem but not sure. Trying to get it fixed ASAP Thanks

C0balts5

Check for dtcs first. Sounds like to me maybe mass airflow concern or map sensor. Only time these cars have fuel issues is when the gasoline direct inject pump fails completely. Then you would have power loss codes and the car would not accelerate. Anytime mine sputters and acts up, usually a sensor failed. Mine did it when the map sensor failed, my downstream o2 failed, or my intake popped off.

C0balts5

The tune is what makes these cars so sensitive, mine is tuned at 23 psi with full bolt ons.

Bazz518

C0balts5

Yeah mine was tuned as well by the previous owner. But he mutilated the car. Car had boost leaks, exhaust leaks,

Bazz518

If the sensors are bad would the car have a code for them?

C0balts5

Should have some sort of code. Make sure to check for pending codes as well and make sure the intake is on correctly

Bazz518

I checked for codes nothing came up on my scan tool. Ill have to check the intake tomorrow to see if something came off. What blows my mind is the car ran perfectly from a cold start when i went to test drive it.

C0balts5

When you go to start it look at all your data. Intake air temp reading, engine coolant temp reading. Might just have to drive it till a code sets. Also obviously make sure your running premium. You may have a 02 sensor that's lazy and since the heater circuit is not bad it's not doing to throw a code right away. The computer primarily uses the downstream 02 readings until it warms up and gets into closed loop. I'm on my 3rd 02. My downstream one that usually fails, not sure if it's because of my tune and that I'm running catless