95 Z28 conv, strong gasoline smell

I have a 95 Z28 convertible, and since I purchased it, I have notice a strong fuel smell around the car, mainly around the back of the car.

I have gotten under it, and didn't see any signs of leaks anywhere, also replaced the fuel filler cap, to see if it would take care of it, and checked the vacuum lines that go to the charcoal canister, and have found nothing yet.

Has anyone run into this problem, and if so what fixed it.

Thanks

Walter

1 of 3 things:

1. Your catalytic converter is clogged, you can either gut it, replace it with a straight pipe, or pop a new high flow cat on there. If this is the case, you'll notice a nice hp gain once you fix it up...

2. You may just be running really rich. Does any black smoke come out when hammer on it, or rev it? If so, you might wanna look into changing your o2 sensors. If they are not functioning correctly, they can cause your mix to fluctuate one way or the other. In your case, it would be to the rich side. If this is the case, you'll notice a little bit of hp gain, but probably not enough to feel it... :)

3. Your engine could be missing. Sometimes it is difficult to tell when only one cylinder is misfiring. If one is misfiring, you would have extra unburnt fuel in the exhaust, which could also make it smell a little.


Good luck...

Thanks for the info, but the smell seems to be around with the engine off, and after I get back from work.

The catalitic seems to be Ok, as for the o2 sensor, maybe, but what I smell, is raw fuel, and there is no black smoke.
By the way, the catalitic runs very hot, and the fuel would not smell fresh out of the tank comming from the tail pipe.

Thanks

Walter

well if it runns really hot, then its probly on its way out. but as far as the fuel smell, when you stomped it, you could have broken something, unlikeley but very possible. is your check engine light on???? its possible that you have a fuel tank system leak, if so it should set a code, because the computer runs vacume tests on the fuel system to test for leaks. dosnt have to leak bad enough for a puddle for there to be a leak, dont suppose youve hit any potholes or speed bumps lately have you???

Typically catalitics run hot, so that they can burn off excess fuel, that is the reason your owners manual says not to park car on high grass!!

No, there is no check engine light, and the gas tank in the 4th gen F body is above and behind the rear end, I believe that you need to drop the rear end to take out the fuel tank.

I am kind on thinking that there might be a leak around the sending unit, or maybe the charcoal canister that sits behind the fuel filler neck might be bad, and it may no longer be doing its job.

I appreciate your input though.

My guess would be a malfunction in the canister purge system. At certain times the ECM opens a vacuum line to the can to clean out the fumes and burn them in the engine. If it gets loaded up it will stink. Sometimes get the opposite, full time vacuum and it will run the engine rich at times.

Tom3,

This sounds like a possibility, do you know how to test the canister purge system?

I have the shop manual, and haven't seen a test for it.

Thanks

Walter

Suggestion: Take it to a shop. whatever they tell you take it somewhere elese and tell them what the first place said and then go from there.

the only way to test the EVAP system, is with a tech 2, at your local dealership, im a tech, what may be the problem is a stuck vent valve. it allows pressure from inside the tank to escape after going through the charcoal canister, if it is somehow lodged open, you will smell gas outside of the car. i think it goes without saying that you have a leak somewhere, duh, but the only way i have found to accurately find it, is with a smoke machine, which again is at your dealership, hate giving that as advice, but somethings are better not done in the driveway, just my two cents.