High idle and gas smell

94 CIERA CUTLASS

MEMBER
1994 OLDSMOBILE CIERA
3.1L
V6
2WD
AUTOMATIC
68,721 MILES

I’ve noticed a gas smell when I took it to get a system (car stereo and subwoofers) installed. I took it back thinking they might have drilled a hole into the gas tank, which was not the problem. Took it to get a smoke test and was told no leaks anywhere, not sure if they actually did it. I’ve noticed that when I open the trunk you can smell it immediately. High idle problem also at times you can hear the car rev up and when sometimes shifting into drive and reverse it has a jerk to it. I take my time driving and am really careful with my car. I take good care of it, but things do happen at times that you can’t control. Any suggestions on what the problems may be that are occurring?

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,867 POSTS

Hi,

Was anything installed in the trunk that would have required drilling? Although the tank may not be damaged, there are fuel lines at the top of the tank that can be damaged. See pic 1 below. Those hoses are at the top of the tank (fuel pump) and run under the vehicle.

Also, I need you to check something else. Since you have an idle issue, I would like you to check for diagnostic trouble codes. This vehicle has an OBD1 system and doesn't require a scan tool. All that is needed is a short jumper wire or even a paper clip. Here is a link that explains how to do it:

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

I have a feeling the idle issue is being caused by a fuel pressure issue (a leak) causing a lean fuel mixture. If there is a lean mixture, it should set a code.

Let me know what you find or if you have other questions.

Take care,

Joe

See pic below.

Image (Click to make bigger)