Hey Guys, Well, finally got the car out today for a "back country road" strech of the legs. Getting to know my car a little better. Smoother and smoother every drive. Alot more time required though I'm sure. Question: I parked back in my garage after running off about 80 miles and a high pitch whistle like sound was coming from the gas cap area? I slowly open the cap and relieved the pressure. No more whistle. Was that wrong to do? Is that normal for that sound to be there? My tank was just about half full at the time. Please chime in and let me know as now I am nervous again or as my girlfirend say "paranoid" (maybe a little). Thanks Mike
As the tank gets low there is often a sonic amplification of the fuel pump that can sound like that. On the Maser, for example, there is a secondary pump that comes on when the fuel gets low. You also may have had a loose gas cap and the pressure was escaping. It's probably nothing BUT if it's coming from the fuel system you should get it checked out esp. if it's a different/new sound. If something is wrong it's a major fire hazard.
Scarey..So I need to take in then I guess? The sound was a high pitch whistle ..not to loud but auditable. When I loosened the gas cap and released just a little pressure it stopped??? I guess I didn't understand what you said, it is normal or not? Mike
I AGREE WITH NAPOLIS...THE FUEL SYSTEM ON A FERRARI IS NOTHING TO TAKE LIGHTLY. WAS THE FUEL CAP TIGHT BEFORE YOU OPENED IT?.....IF NOT, THAT COULD BE THE PROBLEM. ALSO, ARE YOU 100% SURE IT WAS COMING FROM THE FUEL SYSTEM AND NOT THE COOLING SYSTEM/RADIATOR? AT ANY RATE, I WOULD PLAY IT BY EAR. TAKE THE CAR OUT FOR A SHORT DRIVE AND LISTEN FOR THE SOUND AGAIN. I WOULD NOT SUGGEST A REDLINE RUN, JUST A TAME DRIVE AROUND THE BLOCK A FEW TIMES. PAY CLOSE ATTENTION TO ANY FUEL SMELLS. GOOD LUCK!!
It's certainly correct for you to have some concern and ask questions about symptoms like this, but chances are pretty good that nothing is really wrong. The fuel vapor system on the 348 holds pressure all the time, whether the car is running or not, as long as the filler cap is in place. You always get the characteristic "whoosh" as you unscrew the cap and the pressure is released. If you were hearing a "whistle" while the car was stationary, then it would seem that pressure was being released somewhere. In that case, the first thing that would come to mind is simply that the cap was not screwed on tight enough. You don't have to manhandle it, but it has to be tight enough to make a good contact on the rubber seal. And the seal has to be in good shape. Just look at the inside of the cap, and make sure that the rubber seal is there and isn't damaged. It's possible that in the course of your recent engine-out service, that one of the hoses to the charcoal canister, or somewhere else in the evaporative system, may not have been secured properly. I would take a look around at the hoses, just to make sure things look OK, and check for any fuel smell in the engine compartment. There should never be a smell of gasoline. If possible, try to locate the source of the whistle. Cap? Canister? Hose? It's indicating that pressure is being bled off in what is supposed to be a sealed system. Not likely to cause an actual leakage of gasoline, but as you know, fuel VAPOR is highly combustable. Edit: Closeup of system Image Unavailable, Please Login Image Unavailable, Please Login
Thank you so much for your assistance once again. Great detailed infomation. You are a wealth of knowledge. I am heading out to check for the source of the sound. I will let you know what I find. hopefully a loose gas cap?? I apparently need to invest in a shop manual. Many thanks, Mike
Good news I think. Drove her for about 15 minutes. Appears to have been the gas cap. I remember when it was whistling that it twisted off quite easy. No more sound, all hoses and corresponding systems visually appear intact and no gas smell of anykind. I will take out and check after a longer harder drive. Thanks, Mike
All checked out today. Great drive, no whistle. Must have just been a loose gas cap. Thanks for your help guys and yes, any excuse to go drive I guess. Mike
