My 1990 YJ with the 4.0 conversion wont start. The new engine and harness are out of a 1992 Cherokee HO. Upon initial crank it fires off once and then just cranks. The fuel pump primes upon first crank and injectors pulse once (checked with noid light) and then nothing. The fuel pump only pumps while cranking (voltage checked at ballast resistor, 12 V while cranking). The only code that comes up is 41, open field circuit (all wiring checks good, and this shouldnt keep me from running.) I assume the 41 pops because I am cranking and cranking without an opportunity for the altenator to send power anywhere.
It seems anytime I read about someone replacing the computer it does not fix anything. However this is all I can think to replace at this point. I have not heard of the auto shutdown relay fixing anything either, will a faulty auto shutdown relay cause this?
I can get the engine to run if I use ether or pour a little fuel into the intake.
I have replaced the Crank Position Sensor, Cam position Sensor, and have installed the proper Fly Wheel for the engine.
Any help is welcomed, I have exhausted myself with this problem.
Well, it is finailly running!!! Hells Yeah!, Finially. Thank you to everyone for your suggestions and pointers. It came down to the the timing. Yes the timing was off. I guess when we installed the distributor after replacing the Cam Sensor we dropped a gear. We corrected the timing per the Haynes manual and "volia."
I am bouncing off the walls. I was just about to roll the thing off a cliff! Almost time to get muddy!