El Paso Vette

I have an 2002 C5 coupe with 65,000 miles. When I drive there is no gas smell, however, when I slow down there is a distinct gas smell from the A/C vents. After stopping with the engine idling, the smell does not continue. When I open the hood there is no gas smell.
I have researched the problem on the forum and changed the fuel filter and pressed the line from the throttle body back into the fitting behind the engine. Still the problem persists. It tends to be more pronounced when I travel and then slow down or stop. Around town, the problem is intermittent. I have had the gas tanks dropped and refitted with new lines. I don't know what else to do.

c31980

check this purge line

Dcollins3208

Could be leaking header gasket or an exhaust leave somewhere else down the line

El Paso Vette

Thanks, I will check it out.