Strong fuel Smell

[Mark S. 19]

Hey All,

Looking for a little help. I have a 1997 E36 converted to a dedicated track car. It has an S52 swap and from what I am told, was competitive in SCCA events for many years before I got my hands on it. That said, I have driven the car for the past 3 years in New Jersey at NJMP on member days without incident. Recently I have been experienced an overpowering smell of gas that most recently forced me to pit early as the smell was so strong it began to impair my ability to drive. Additionally the car has started to devour fuel like it was going out of style (30 miles, 10 to 12 gallons of gas). The car idles fine and pulls strong on the track, but it is definitely suffering from some type of fuel issue. I have examined the exhaust system, and the exhaust pipe is clean (no heavy black exhaust deposits and if anything almost looks white) and I have examined the fuel lines from inside the cockpit (removed the access covers) and do not see or smell any signs of leaking lines or gaskets. Lastly, I have pressurized the fuel system (run the pump) and do not see any visible signs of leaking.

Is there something I am missing or somewhere else I need to look?

PS. I have had a buddy follow the car on the track and there is no visible signs of fuel running out of the car.

Thoughts ?

Thanks.

[jimmypet]

What is the state of the fuel system?
Cell?
Stock Tank?
What is the state of venting system?
If still stock do you still have the charcoal canister and purge valve?

[NoLastName]

When this happened on mine it was caused by a damaged vacuum hose on the purge valve. The MAF sensor rubbed a hole in the vacuum hose to the valve, and the fuel system started siphoning fuel from the tank into the charcoal canister. Raw fuel was venting out the tube at the bottom of the canister. The smell inside the car on track was quite overpowering. If you still have a charcoal canister/evap system, check for evidence of fuel dripping onto the driver's side front control arm from the open tube above it. If you see that, pull your MAF and look for a torn vacuum hose at the arrow location below. You can see how the MAF boot is resting right on the vacuum line in this photo. I had to shift things around and pad the vacuum hose to prevent it from happening again.

IMG_0796.jpg

[RMF]

I recently had a similar situation at VIR (no irregular consumption, though)on a stock-ish 328. After driving there 7 1/2 hours, with refuel and without issue...filling up at the track between sessions, I had a very hard time filling it (the nozzle kept clicking off), I had to pump it REALLY slowly to fill. Towards the end of the next session, I started smelling fuel. I ended up tracking down some wetness on the inside of the trunk back by the battery(it's gutted of carpet already) and some spray out of the fuel door..when I cleaned that up it was fine the rest of the day. I inspected the filler the next day and my best guess is, the 20yr old rubber hose that connects the plastic filler tube to the tank would collapse when it was hot and not letting fuel in. I was more careful filling on day two, and didn't have an issue...and driving home also didn't have a problem.