Hi All, New to this forum as I have just purchased a 1990 F348tb... Although I plan to completely restore it over the winter, I'd like to put a little mileage on it "the way it is" for the rest of the summer but there are two issues: First is that it absolutely stinks up my garage with gas and exhaust fumes (while parked overnight) and it spills into the house. I have made sure that the gas cap is on tight and a quick sniff reveals no smell around that area and there are no puddles on the garage floor. I'm just wondering if it's a common issue with 348s and if there are things I can do to limit the smell... right now, I leave my garage door open about 5-6 inches to allow the fumes to escape. Second is that at highway speeds, I hear a buzzer sound on and off when traveling over 100km/h (60 mph) and I can't find the source... I can't even tell if it's coming from the engine area or behind the seat because of all the road and engine noise... I've checked oil level, coolant level, coolant temperature, oil pressure (but oil temp gauge does not work). I've driven the car in city traffic and haven't heard the buzzer once... I get on the highway and sure enough I start hearing it... Any ideas on what it is? Thanks DF
Don't drive your car if you smell fuel: http://www.club348.com/technical/Tech/348.html#FuelSmell Of course, if you are smelling partially burned fuel because your car has hollowed-out cats (or straight pipes in lieu of cats) then that's a different story. As for your "buzzer" sound: does it change in pitch as you increase your RPMs?
I am not aware of your problems or know them to be normal. I would be disappointed if my car had these problems. I am sure someone will assist you with your problems soon. This is a great source to resolve any issues. Darryl
Sorry, I should have mentioned that the cats have been replaced by straight pipes... Thanks for the link... I will check those things asap. The buzzer sound does not change pitch with RPMs but it does stop and then start again... DF
I would suggest that you may have a bad non-return valve and/or a bad cut-off valve in the exhaust air injection system. This could account for the buzzing noise, if the diaphragm is flapping under some conditions, and it could account for the exhaust smell, if the air injection system is operating when it should be shut down. I recall a thread where someone found that his cut-off valve had melted. Why does your car need to be "completely restored"? Tell us about it! By the way, a faulty oil temperature reading is usually caused by a bad ground at the oil sump tank - easy to check, easy to fix. And welcome to Ferrari Chat! Edit: This is the thread I was thinking of: http://74.86.28.138/~ferrari/forum/showthread.php?t=142985&highlight=147390
Miltonian, would it be correct to say that if you have one or more faulty non-return valves, that you'd be getting extra air into the exhaust in front of an O2 sensor, causing the O2 sensor to read "lean" even if the mixture was fine...thus having the O2 sensor erroneously tell an ecu to enrich the fuel mixture?
I agree with what you are saying except that a faulty non-return valve will not cause excess oxygen in the exhaust system as long as the cut-off valve (and the system operating the cut-off valve) are functioning properly. The non-return valve (#2) simply prevents exhaust gases from flowing back into the air cleaner housing. The cut-off valve (#1) opens during warmup to allow extra air into the exhaust system. It is supposed to close after the coolant reaches 50 degrees centigrade (122 degrees F). If the cut-off valve remains open, the extra air "fools" the O2 sensor as you describe. Image Unavailable, Please Login
I agree with what you are saying except that a faulty non-return valve will not cause excess oxygen in the exhaust system as long as the cut-off valve (and the system operating the cut-off valve) are functioning properly. The non-return valve (#2) simply prevents exhaust gases from flowing back into the air cleaner housing. The cut-off valve (#1) opens during warmup to allow extra air into the exhaust system. It is supposed to close after the coolant reaches 50 degrees centigrade (122 degrees F). If the cut-off valve remains open, the extra air "fools" the O2 sensor as you describe. it that what makes that funky noise when things are warming up? it goes away after a few minutes. sometimes one side quits first....
Had the same fuel smell. Follow the link that No Doubt provides. For me it was the a small crack in the filler hose to the gas tank. A simple and inexpensive fix
Could the charcoal cannister/evaporative emission control system be the cause of the smell? Double check all the hoses and fuel pipes in the area between the rear spring and the bulkhead. Cracked fittings on the high-pressure braided fuel lines are possible if the fittings are over-tightened (there was a recall to replace the early-type hoses). Failed fuel pressure regulators can leak fuel into the vacuum sustem. Easy to check for (Im' sure it's covered in the link No doubt posted). Double and triple check for leaks - a small one will evaporate long before it makes a puddle on the floor. If the cause of the fuel smell is 'internal' (over-rich/stuck injector etc.) I would expect the end of the exhaust to obviously smell of fuel (sniff with the engine off - unless the problem is really getting you down...). I get a buzzing/resonance behind my left shoulder at 50+ if I have the window half way down - I have concluded in my case it is just some trim vibrating in the breeze.
I am having my catalytic converters tested also and I don't have any lingering smell of fuel in the garage. I would definitely get that checked out before putting many miles on the car. The last thing you want to see is flames in the rear view mirror. Buzzing - no idea, but I would not worry about it much. Pictures??? BT
Me too . We only got mandatory cats in the UK around 91' though so everybody over 30 is used to how exhausts smelled 'back in the day'.
Buzzing noise could also be a non functioning tank vent system. Check to be sure the vacuum lines are hooked up to the engine at the front of the intake plenum, and the 2 electrical connections that are on the side of the canister are connected to the solenoids. Check your fuel lines as well. Make sure that the fittings at the fuel rails and at the fuel filters are not cracked. The fittings are made of a very soft aluminum and if over tighten they crack and leak. Ferrari has a recall in place for these lines, and will replace free of charge. Do not drive the car until you have found the source of the fuel smell!
Hi All, I finally found the source of the fuel smell... it is the fuel level sending unit that is cracked and leaking... seems the undertray protecting the fuel tank is missing from this car and something must have struck the fuel level sending unit. Has anyone had any luck with universal sending units? Or should I go with OEM? Guess I'll have to make a fiberglass under tray as well. The buzzer sound I haven't yet found but I now suspect is an aftermarket buzzer that rings as I've discovered rings precisely at 120km/h (and above) and stops below it, regardless of engine speed or gear... sort of a reminder not to press too hard on the accelerator at highway speeds... I'll have to disable that... JQP
Not wishing to hijack thread - but re exhaust non return valves - why do some 348 motors have two per side and some one per side? My 348 is UK spec / build, original motor and has two per side fitted.
What kind of dumb-ass installs a speed buzzer on a Ferrari!!!! Did Ralph Nader previously own the car?
Our non-return valves permit outside air to enter into our exhaust (but prevent exhaust from going into our air intake, hence the name "non-return" or "one-way" valves). No doubt as emissions standards tightened, more fresh air was required to cheat (legally) official emission exhaust sniffers. As more fresh air goes into our exhaust, the percent of hydrocarbons, carbon monoxide, and ozone parts per million decline. Of course, our cars are still emitting the same *number* of HC, CO, and NOX...but the percent per million declines because we are pumping more fresh air through our exhausts. So going to 2 or 4 one-way valves just means that our "parts per million" decline when measured at the tailpipe.
Should the "arrow" marked on the cut off valve point towards the exhasut or towards the air cleaner assembly?
The arrow for flow should point to the exhaust (though my one way valves are so old that I can't see said arrows).
Hmmm......Interesting. The reason i ask is that one of the non return valves fractured recently and i had to replace. In doing so i'm sure i noticed that the arrows on the cut off valve (both sides) point towards the air cleaner. If these are fitted the rong way around - what affect will this have?
I would expect that they'd permit hot exhaust to melt the plastic cut-off valves in between the non-return-valves and air cleaner if they were somehow installed backwards, but is that even possible to do?
