Ok, It's time to figure this one out. What do we know? The car ran before the service, so something has been changed during the service that has caused the engine to not run. We know the engine has spark, if quick-start spray is sprayed into the intake, the engine will run. In order to have spark the Motronic control unit must have power, ground, speed and phase sensor inputs. If the Motronic control unit has all of the information to generate a spark, then it should also fire the injectors, but it doesn't. What are the possible causes? 1: No power to the injectors. There is a relay under the passenger footplate that supplies power to the injectors. If you unplug the connector at the fuel injectors, there should be constant 12V power on one pin of each injector connector with the ignition key on. If there is no power, you need to trace the problem back to this relay. 2: No ground to the injectors. When the Motronic control unit fires the injector, it grounds the other pin on this injector connector. You can purchase a little light (known as a "Noid Light") that will plug into the injector connector in place of the injector, so you can see the injector pulse, or you can just listen for the injector clicking with a mechanic's stethoscope. The Motronic control unit gets its ground from the wiring harness that grounds at the rear of the 1-4 cam cover/head. If this is disconnected/loose, it will cause the injector to not fire. Check which symptom you have, and we will go from there. What relay did you replace and why did you replace it? Brian B.
No pulse to the injectors. No turn-on signal to the fuel pump relay. ...but, you've got spark because the engine turns after spraying starter fluid. That tells me that the Motronic ECUs aren't dead and aren't purposefully disabling the engine (e.g. shutting down banks). The obvious remaining single cause of both "no injector pulse" and "no fuel pump relay turn-on signal" would be the fuel pump inertia switch (and they do fail).
Thank you for the reply, I have no power to any of the injectors, all relays under the kick panel check out as ok. Could you tellme more about the fuel pump inertia switch. Thanks
http://www.rockauto.com/catalog/x,carcode,1104040,parttype,10756 That bad boy stops your fuel pump if you are in an accident that kills the motor.
That's BS a car will run on gas over a year old easily. It may stumble a bit on start up but once it's running and warming up, it'll be fine.
The gas is all new. The issue here is simple. No injector pulse and no fuel pump acivation. All fuses and relays are working.
Was reading to find the eventual fix for this but then the thread ended with no result. I know this is an old thread but would be nice to know what was wrong as im having a problem with no injector pulse as well.
Is that the only symptom? So you have cranking, you have fuel pressure (fuel pump is running) and you have spark? FWIW, the 355 does not have an inertia switch. These first appeared on the 360 and V12's.
2.7 , no immobilizer. New fuel pump, its not the crank position sensors or the relays and there is spark.
Do you have 12 volts at the injectors with the key on? If you have, then it's an ECU trigger issue, not a power issue. (EDIT: is it one bank or both?)
If injector relays O and L are working, than you should have power going to the injectors. Relay O and L should also illuminate the CEL/SDL lights on startup. Relay O and L also send power to the coils of the respective fuel pump relays (P & M). The pump relays also provide power to the O2 heaters. Relay O and L should send power to things like the MAF, Cat ECU and Idle Speed Regulators. I'm told you don't need cranking to get the pumps to work (like you do on the 5.2).
