Check engine light
Thread Starter
5th Gear
Joined: Jul 2010
Posts: 5
Likes: 0
From: Louisville Colorado
Check engine light
I've had my 2004 C5 for less than a month now. It has under 23K miles and is in great shape. Sunday on a short trip home from the local grocery store, the check engine light came on. Two things I did earlier in the day: Filled the car with Premium fuel and hand washed it.
Thanks to this forum I was able to retrieve the diagnostic codes from the car. It did not have any codes marked as "Current," everything in the computer was followed by an "H." The only two codes listed for the PCM were P0171 and P0174, Fuel Trim System Lean Bank 1 and 2. I do not think any of the other codes would be associated with the check engine light.
Could this mean that I didn't put the gas cap on correctly after filling up? I did try to take it off and put it back on correctly, but the light is still on today. If this is the case, will the light go out eventually? More importantly, given these codes, should I take the car in somewhere to get it looked at further?
Thank you very much in advance for whatever help you can provide.
Thanks to this forum I was able to retrieve the diagnostic codes from the car. It did not have any codes marked as "Current," everything in the computer was followed by an "H." The only two codes listed for the PCM were P0171 and P0174, Fuel Trim System Lean Bank 1 and 2. I do not think any of the other codes would be associated with the check engine light.
Could this mean that I didn't put the gas cap on correctly after filling up? I did try to take it off and put it back on correctly, but the light is still on today. If this is the case, will the light go out eventually? More importantly, given these codes, should I take the car in somewhere to get it looked at further?
Thank you very much in advance for whatever help you can provide.
Thread Starter
5th Gear
Joined: Jul 2010
Posts: 5
Likes: 0
From: Louisville Colorado
Thank you for the quick reply. Although I did use Premium, it was at a Valero station and the price was a little lower than elsewhere. Have other folks had issues with Valero gas?
I will check connections around those areas. If I clear the codes, will the check engine light go off? Sorry I am new at this.
I will check connections around those areas. If I clear the codes, will the check engine light go off? Sorry I am new at this.
