Questions and Answers
BMW Takes A Leak
Q. Hi Vincent! I've just purchased a BMW 316i, it is manual, has ABS, made in 1993. I bought it second hand it has already done 187,000 miles. I've just had it recently serviced and have had the camshaft and tappets changed. It runs beautifully now BUT there is one major problem!! That is I have a fuel leak!
You see, when the car is started from a cold engine, there is the smell of petrol. However, recently we have experienced tremendous fuel leakage BUT the mechanic has no idea where it is coming from and if the car is switched off and left for a few minutes it stops!! There is no evidence of a leak what so ever!! Its like a ghost, I don't know what to do and so doesn't the mechanic! Do you have any ideas?? Please help, reply soon ASAP! I will be very grateful for your help!
A. A fuel leak on a fuel injected car really scares me. I was at a BMW dealership in New Jersey a few years ago and we had a BMW 530i towed in. It had a fuel leak and it caught fire. It was a mess, windshield cracked and melted, fenders warped and twisted and everything in the engine compartment was unrecognizable. Damage was about $14,000.00.
If you and your mechanic are 100% absolutely sure there is no fuel leak, then the smell is coming from the evaporative emission system (EES). The most common reason for this happening is the filter for the charcoal canister is dirty and plugged up. Since air can not be drawn into the system, it sucks fuel instead.
The filter is easy to change, just remove the canister and turn it upside down. There is a flat fiberglass filter about five inches in diameter tucked into the bottom. Grab the filter with a pair of pliers and pull it out. Then tuck the new one into place and reinstall the canister. That should get rid of the fuel smell.
If not, then you will need to check the EES for cracked lines. There is a liquid/vapor separator near the fuel tank with lines going to the fuel tank and forward to the carbon canister. There is a purge valve located on the Air Flow Meter that may be stuck open as well.
Please, be 100% sure that there is no fuel line leaks, even if it means taking something off to get a good visual of the lines.
Additional Information provided courtesy of ALLDATA
