158Sierra

I am doing an engine conversion, installing a 3.2 Motronic engine in a 79 SC. I have a supposedly running donor engine. I have the engine installed, installed the Motronic wiring harness and connected everything. I have verified compression, distributor timing and ignition wiring. The engine turns over and I have spark correctly timed, so as far as I can tell the engine speed and reference sensors are working (I measured them and the ohm readings are correct). The fuel pump is running and I have fuel pressure. The fuel injectors, plugs and ignition wires are new. I have 12 volts to the fuel injectors but the injectors do not pulse. I used a light bulb at the injector plug and do not get any pulses when cranking the engine. Also with the Ignition in the on position I get 12v on both of the pins on the injector plug. As far as I can tell this indicates a problem internal to the DME. Does anyone have any iSight on this problem? I could use some additional ideas on things to check. Thanks for any assistance.
Mark

76FJ55

When you are checking for voltage on the injector plugs, do you have ll the injectors disconnected? if you have any of them still plugged in you will see voltage on both pins as the injector coil will pass voltage to the "ground" side going back to the DME. the injectors should have constant power and pulsed ground through the DME.

If you've got +12V with all the injectors disconnected then you have a harness or DME problem. try disconnecting the DME and see if you still have +12V on the ground leg of the injector harness.

Matt1982/4

did you ever find out the problem? i am having a similar issue

theiceman

an early lesson .. dont by cheap **** aftermarket parts for your Porsche.