Just out for lunch and one bank has gone down and no rpm on the instrument panel. Checked fuses, swapped relays and same result! On starting and running I can hear and feel the left hand fuel injector relay clicking away. Pulling the relay doesn’t affect the running. I would search the forum in detail but out and trying not to get another tow truck out! Any ideas appreciated. (I’ll search in detail when I get home!)
Sorry, I don't have a 348, but most of the USA is just waking up and probably not a lot of replies yet. Anyway a quick search looks like most people try swapping banks side too side, but that never seems to work. It appears that even a little fault will put the 348 in limp mode, where it will intentionally run on one bank. Many things can cause the limp mode, one guy said it was a sensor Image Unavailable, Please Login If I was you waiting trying to decide on a tow truck or not, with no tools etc start by unplugging and replugging in all the electrical sensors you can find easily. It's possible one may have just lost its connection due to a tiny bit of corrosion and thus it put the car in limp mode. If that doesn't work to it and troubleshoot later. Many of the research results said their bank shutting down issue was intermittent. It's possible that yours is well, your just in the middle of it now lol. maybe when you parked the car, the engine bay became heat soaked and a component went haywire. It's possible that once the car cools down a little longer it might work long enough to avoid a tow Hopefully a couple 348 guys chime in
Faulty left bank crank sensor? I recall that this supplies data to the tacho (via the respective ECU). It's not the bottom sensor, but the one on the "side" (at 9 o'clock). I think both are hard to get to without lifting the car. If you can get to the crank sensor, check the plug for contamination. Not really sure why your relay is clicking. The ECU controls the relay. Hope it's not an ECU. (EDIT) Are you sure it's not the fuel pump relay clicking? When the ECU senses the engine rpms at 30 revs, it turns on the the respective fuel pump (via the pump relay I presume). If the crank sensor is faulty, it may not see a consistent value above 30rpms and turn off the pump.
What 'Qavion' said.... The only other thought for a quick try would be a Reboot.... Power disconnect for 15mins.... allowing the ECUs' memories to clear, power up and hope!
Photo of the crank sensors... Image Unavailable, Please Login Image Unavailable, Please Login Upper sensor, but lower plug. Look for wiring damage and oil contamination.
Thanks all. The above was my thinking or a damaged wire somewhere. Engine has just been out, but I’ve done 200 miles since without issue. Oil damage on sensors might be relevant (long story and now fixed!) Hopefully limp home and then figure it out in slower time! (Need a lift!!!!)
Does the SDL light come on? One of the most common failure modes of the Cat ECU is a stop engine signal with no light what so ever.
Cat ECUs are disconnected, so isnt them. Tried truning the power at the main switch off...didnt work! Seems odd left bank down, left hand injection relaying clicking away (double checked, defiantly this relay; pulled it on the ride home as thought it cant be doing any good clicking away!) and the RPM dial not reading as well. Back home now, seems I'm still faster than everybody else, even on 4 cyclindrs. LOL Once its cooled down I'll start digging; first port of call the crank sensors! Thank you all for the quick suggestions/ help, it is much appreciated.
With ignition on, the ECU runs through a quick self test, then activates the injection power relay. This is prior to engine start, so it's not yet looking at the crank sensors (or at least not the revs coming from them). It sounds like the ECU is not happy even before starting the car. Is the relay actually clicking just with the key on?
All sorted!!! Ian, you were very much along the right lines, thank you for the pointer. 1) I pulled and visually checked the connections on the crank sensors, all fine. Engine still running on one bank. 2) I pulled the fuse panel and checked everything there and no visible signs of overheating etc. Engine still running on one bank. 3) I then went to swap ECUs, taking the left hand bank out, there were a couple of temporary connections there (not to the ECU but to the main harness, one brown/black one yellow (I think)) whcih were jumping ove the main connector, so jiggled those, ran fine!!! Jiggled them again and ran on one bank! I cut the old temporary connections out and re-did them, runs fine!! I'm hoping its those rather than one of the wires fraying as it gows through the bulkhead or into the ECU connector. Former looks like a fairly straight run so fingers crossed thats ok; as I can see that being an engine out job, or at least plenums off and a lot of cursing!!! Whilst its on jacks and the undertray off, I'll check the continuity of the alternator wire up to the engine bay connector and then put the trays back on. At least you can get the harnesses from Ferrari, not cheap, but you can get them if needed!!! Again, many thanks for taking the time to help me out, its hugely appreciated....great forum = great people!
Can you elaborate on the "a couple of temporary connections there"? Its the first I heard of these. Do all cars have these or was it something specific to your car for some reason?
Something specific to my car. It would appear, for whatever reason, two wires that should go through the main connector had been cut and the connector bypassed.
Brown/black is a typical wire colour used on Ferraris for carrying tachometer data from the ECU to the rest of the car (including the instrument panel). I'm not sure why a problem with that would cause the engine running problem. All the ECU needs is the raw data from the crank sensor for rpm. The yellow wire may be a yellow/black wire. This sends power to the coil pack and ECU (a more likely scenario for engine running problems). A white/black wire controls the relay. I think you were lucky to find the problem. Old electrician rule: If in doubt, go to the last modification
