Hello chaps My 348 has an issue and im posting here in the hopes someone can give me an idea of the “common” issues these cars have which could help identify what is wrong Last drive out in my car the power just went, Ive taken the car to some mechanic friends and each one of them sais there doesnt sound to be anything majorly wrong with the car, possibly fuel or electrical. The car hasnt dropped a bank, Put your foot down in 1st gear and its like your taking off in 4th the powers just flat Today im going to replace all the relays and go from there, any help will be greatly appreicated
Are you certain it hasn't dropped a bank? 1) Is one of the slowdown lamps illuminated? 2) Do the slow-down lamps actually have bulbs installed? You'd be surprised what some folks do to these cars...
3 seperate mechanics have looked at it and all said both banks were running, the slow down lights light up on ignition but then dissapear after a few seconds May or may not be related but the front right headlight bucket stopped going all the way down the same night the problems with the engine started, aswell as some other electrical faults which have now been resolved other than the headlight, speaking of which has today developed another fault whereby both headlights are out of sync, the bucket on the right is up when the left bucket is down
The issue is permament, it a struggle to build up speed in the car so limp mode comes to mind When its been revved, once you stop reving the motor tends to stall Today ive replaced the relays, disconnected the cat ecus and disconnected the maf sensors, aswell as a ECU reset, still have the problem
Too many questions... e.g. where are you located, how long have you owned the car, any other recent work/events (theft, crash, flood, etc.), are your mechanics knowledgeable on the 348..........
United kingdom 12 years One of the mechanics is a close friend whos worked on my car since i bought it. 1993 2.7 Yes i have the workshop manual online
So, it revs freely while in neutral or the clutched disengaged? Do you get any codes from the ECUs behind the seats? Check this thread if you don't have the test buttons. https://www.ferrarichat.com/forum/threads/348-diagnostics.511462/
Sometimes after giving it a rev, the revs will drop so low it stalls, not every time but most of tbe time. This also happens out on the road
Did you do a compression test? Change out the plugs for laughs? Sent from my VS990 using FerrariChat.com mobile app
I would not ignore that electricity - headlight problem. Start with making sure your battery is good, and the alternator is good.
No i havent performed a compression test! The plugs were replaced in feb along with a new battery, ive done an alternator test and im getting just over 14v so thats ok. Im not ignoring it, can anybody see how the two could possibly be related or merely a coincidence the issues happened at the same time? Ive also been advised that although both banks are running when idling/revving, one could be dropping when driving, although the engine doesnt sound happy to start and still cuts out when the revs drop when in neutral so i really do not think i have a bank dropping under load?
So you checked out the battery and alternator, good. Now check the fuel pressure at the fuel filters and at the injector rails.
has a tensioner gone bad and the timing belt skipped a tooth? the only way I could even possibly think to check this is to pull the valve covers off and see if the assembly marks are close to the rightplace.. sjd
You have lost a bank of cylinders. Just because you have spark..does not mean you have fuel going to the injectors. The cat ecu will chop fuel, not spark. Start the car, and pull an ignition wire from one side of the engine. If you pull one from the running side, she will stall. Not so on the side that is not running. If found one bank is dead..start swapping components from side to side until the effected bank come back to life.
Thanks all for your suggestions, noted. The moment the power went, there was no sudden bang/noise or anything that made me think what the hell, just literally had the power zap away, i was turning at a set of traffic lights so low speed/ low rpm when it happended, there was a slight hesitation about 4 miles beforehand under acceleration ( not hard acceleration) which lasted a split second. i cant recall if the electrical gremlins happened at the exact same time although they werent present at the start of the journey and have been ever since, in talking headlight issues and half the dash wouldnt illiminate . A short was found which fixed the dash lights. My mechanic is under the impression the issue with the engine is an electrical one
I’m ordering a compression testing kit with comes with the following thread sizes M10 x 1.0 mm M12 x 1.25 mm M14 x 1.25 mm M18 x 1.5mm Can anyone confirm if any of these are the correct size or if not what thread size I need?
You can get one of those infared temperature guns fairly cheep. Could easily tell if there was a cold side to the engine. I'm no expert but based on the headlight gremlins I would look at, inspect, and clean all of the grounds in the car. Do you have a wiring diagram? Spend some time looking at it. See where the grounds are, also see if certain parts of the engine management and headlights share a common power supply/component.
I've had this problem twice in 10 years. Both times it was an O2 sensor. Edit: with the bad O2 the car started perfectly, idled ok, but no power. Other sensors I've replaced: Car hard to start, but ran well after warming up = coolant sensors Car difficult to start but ran perfectly after it started = cam position sensor Car hard to start and ran like crap = crank position sensors
I speculate that you have partially blocked fuel filters from disintegrating rubber cushions around the fuel pumps.
I own a F348 for over 16 years, my recommendation: As a starter measure/verify with a multimater the following: - Battery voltage should be around 12V engine not running With engine running: - Battery voltage should be higher than 12V and 14.5V max - Headlights voltages can be easily measured at the left and right bulb fuses with main/dipped beams switched on (luggage compartment fuse box, fuse 1, 2, 11,12) measured voltage should be very close to the actual battery voltage when beams are on. (see workshop manual) - The "Step Pad Fuse Box" is more important, measure voltages (with heated rear switch on) on fuse number 8, 14, 18, 19 and 22 - Make notes of every voltage for each fuse) >> for example if motormanagement/sensor or fuel pump voltage is too low the engine will run and rev but not produce power, 1) due to low voltage issues with motor management sensors, the motor management receives incorrect information and provide incorrect open/close fuel injector timing. -2) due to low voltage the fuel pump don't produce enough fuel pressure. Hence no extra fuel can be provided to deliver extra power. Next: - Please start to study from C24 (operating principle) in the 348 workshop manual to make yourself familliar with the startup procedure, motormanagement and sensors. (as mentioned t1, t2, and t3 sensors) - Check Grounding on different sensors electrical points (see electrical schematics workshop manual) - look for +12V voltage points in the electric schematics (see workshop manual), particular around motormanagement components - Verify (the positive +12) voltages on different electrical pins on motor management and sensor components My best guess , you have a voltage problem in both (left/right bank) motor management systems/sensors fuel-pump related to a failure in the "Step Pad Fuse Box" of grounding problem. Rob