Dear Car Talk:
I have a very puzzling and SCARY problem with my 2004 Chevrolet Trailblazer. About 6 months ago, it started to have a gas smell in the cab when the engine was started. It would dissipate in about 10-15 minutes. It didn’t happen often, but I mentioned it to my mechanic who said he had never heard of that. About 2 months ago, it started happening again and the occurrences are more numerous. It happens whether the gas tank is full or 1/2 full; and now, the fumes are coming from the air conditioner vent. Sometimes it smells strongly outside and inside as if someone is pouring gas inside the vehicle and it scares me as to whether the vehicle could catch fire! Of course when I take it back to the mechanic, the smell has dissipated and even leaving it with them for days reveals nothing. It doesn’t happen all the time, but when we start up the car is when we have the problem. HELP!!