My 95 355 rpm is exactly double what it is supposed to be. 2000 rpm instead of 1000. What sensor provides the RPM signal to the ECU? The crank sensor or the phase sensor? And what ECU (left or right) makes use of that signal to control the engine? The tachometer is fed off the left bank (5-8) ECU. So, I know that.
This is not going to help you. Leave it because now you can tell all your friends your ferrari revs to 17000.
Hmm, not sure that's the problem.... My car dropped a bank and threw a code for the bank 5/8 sensor. Tach still worked. Not sure if that's where the tach signal comes from and if it does, your engine wouldn't be running right on one bank - you'd presumably get double the fuel and possibly backfiring on that side if it were reading 2x the pulses. Of you want, I'll unplug my bank 1 sensor altogether and see if I get an rpm reading on the tach - unless the ecu is smart enough to realize it's bad and switch to the other bank sensor?
I got to start somewhere. New O2 sensor, no change. Another MAF, no change. Disconnect battery, relearned ECU, it works until the first time you shut the engine off, then no change Coolant temp sensor, new, no change. So, it's the ICV, or TDC, or wiring messed up. One thing at a time. What's left?
I think i would change the bank 5 sensor. According to earlier in the manual allthough the 5-8 sensor is used for timing the 5-8 bank the 1-4 sensor governs. On my car i only have the 1-4 sensor. If the 5-8 goes bad car will still run timing being set by the other sensor. If the 1-4 goes bad i think the car shuts down or something. I cant remember for sure.
Actually afte re reading it it seems like it uses a combination of both to confirm timing on cylinder 1 and then uses firing order for timing after that. So neither governs. I would still change the num 3 from diagram. Or the 5-8 sensor because as you said this is the one that provides output for the rev counter. I would not go for the bank 1 sensor.
Why wouldn't it be the tachometer itself, especially if the engine is runnning well? I have heard on non-Ferrari forums that tacho failure can cause double rpms (although I don't understand why it would work after an ECU reset, then fail again)
PROBLEM FOUND AND SOLVED. I hereby apply to the Stooge leadership to rescind my stoogeness title. In the engine out I just did, I refreshed over 150 crimps on the wiring harness and for the Idle valve left bank (5-8), I reversed the order of the wiring 1-2-3 instead of 3-2-1. The idle valve is therefore always on. This explains the error 1211 at idle on that bank because the computer richens the mixture (I smelled it) but cannot compensate for the idle valve always on. And, the idle is 2000 rpm instead of 1000 rpm. Found it, swapped it back, and all is well now. Steady idle at 1000 rpm.
I dont read Mitchell writing. From what you said originally i thought your rpm was allways double. Hence my comment about 16000 rpm. Glad you found it. Cool thing is i learned the 95 has an xtra sensor.
You also would have been corrct in your original diagnosis if you did like many others and just blanketly blamed the mechanic ha ha.
I am proud of the fact that if there is any screw up, it has always been me. Easy to identify who is at fault. But it only goes to show that re-wiring the harness takes all the attention you have. I even wrote down the wiring color in my notebook correctly, and put the wires in backwards.
Been there and done that. When i did my major i was quite relieved when the car started and ran better than before. Until i got in it and saw the water temp didnt work. Same as you crossed the wires to the temp sensor. This happened to be the first connector i changed from the gold kit. As i said i was happy everything worked corrctly. That friggin main ecu plug is a $itch though sitting in the car. I left it until the engine was back in.
