Hard crank and cam faults

[94pgt94]

Car started as an obd1 probe gt.

Engine is:
Ze block and pistons
Kl31 heads
Kl01 cams

Ever since I put this engine in I have had hard cam and crank faults. I tried 3 crank sensors and 3 different distributors. These faults still remain. The car runs and drives pretty good. Starts no problem.

To me, bad crank sensor should keep the car from running.

Ivebeen through tons of different solutions, can't make it any different. I think I might be over thinking it and missing something stupid.

If I put the car into diag mode and try to turn the disty for timing, it makes no change. The engine is timed, checked it 5 times at least, but no adjustment through disty.

Erik

[KLZE Porsche]

You are missing one of the crank sensor inputs. It sounds like you got an OBDI harness that requires both signals (I believe a 93 -but may be both 93 & 94) and it is likely that you are missing your signal from your distributor or crank sensor. When you loose this signal -your engine will run still -but in what is called the "limp home" mode. This is where it fixes your timing to a static 10° and your fuel air mix also to a static mixture.

The OBDI car that requires both signals -compares the signals to adjust the timing accordingly. But when it cannot compare both signals (as in one signal missing or faulty) -it then switches to the limp home mode.

If this is the case -you are getting nowhere near your maximum performance. So you need to troubleshoot:

1) If it is 93 or 94 OBDI (or possibly both years) that require both sensors (I know it is not a 95 because a 95 requires only one signal).
2) Which year your harness is
3) If you have the correct distributor -matching the year harness
4) If the disty or crank sensor are bad for crank signal output
5) If your harness is bad (loosing one of the two crank signals)

When you are in the limp home mode -you will not be able to adjust the timing -since it is fixed to a static 10°.

P.S. I just re-read and saw that you said you changed 3 distributors and 3 crank sensors with no luck -so it sounds like it might be time to start checking the wiring:

http://www.xtremethings.com/Engineer...ring-(ECU).pdf

Pages 25-3, 25-5 and 25-9

[94pgt94]

hey! I saw that you saw my engine harness wanted add as well. this is why i was looking.

the harness is a 1994 atx probegt harness. the one the car came with.

the disty is correct for the car. the crank sensor is as well. used an ocsilloscope(i think it is called) at work and pinned the crank sensor. it is reading correctly.

the car may be in limp mode, but doesnt feel sluggish. its boosting at 4.5 psi and it is pretty strong. im going to dig deeper into the wiring.

you may be correct that on of the 2 signals is not getting through to the ecu. No matter what i do, i am stuck with these 2 faults.

Thanks for your help! i will keep digging!