I could really use some advice on where to look. I have a 1987 Toyota supra and it cranks but doesnt start. I checked my CPS and it checked out good resistance wise.
CRANK NO START
- Thread starter luffy1124
- Start date
Welcome! You've come to the right place. Have you pulled your codes yet? Search on here for instructions, off the top of my head it's installing a jumper on T and E1 in the diagnostic plug then counting your CEL flashes.
With the CPS, I've experienced a problem where the CPS itself worked, but the original CPS wiring harness was old and brittle and the CPU wasn't receiving the signals; I would check to make sure that is ok. You can buy a new CPS harness from Driftmotion for petty cheap. Not saying that's the issue, but you may want to check that the signal is making it to the ECU.
Thank you both I will do both of those things because I do have a check engine light and my entire wiring harness looks terrible. Also will one bad injector stop my car from running. I ask because I decided to put a new full pump today and when I got done I checked if I was getting fuel to the fuel rail and I am. I then proceeded to check resistance of each injector and got 3.3 ohms on all of them except for one that had 45ish ohms.
First thing. Check if your tach shows life when cranking. If it does the ECU is getting CPS signals and firing the ignition. Next step is to confirm spark. Then confirm fuel pressure.
I jumped my diagnostic plug and my CEL did not flash at all and I also looked on drift motion and could not find the harness. I took everything off of the top of my engine to get to my harness that is under my throttle body running next to my fuel rail. Should I cut into it and check my wires there? I can not seem to remember if my tach moves but when I put my car back together I will check. Once again thank all of you I appreciate any help.
Ohhh no cutting into something seems like a terrible idea when you can’t even get your codes yet. Figure that out first.
CPS likely will not trigger any CEL's.
Coil resistance does not tell you the whole story.
I would check the CPS waveform or as Pi suggested above, is your tach moving during cranking?
Coil resistance does not tell you the whole story.
I would check the CPS waveform or as Pi suggested above, is your tach moving during cranking?
Well I pulled everything off the top of my car and got my harness out and started looking at it and whoever had this car before butt spliced every gah damn connector!!!! I started pulling on splices to check and more than half of them pulled apart barely hanging on by a strand. Also the amount of nasty cheap black tape is astounding. Really at a loss the harness looks terrible. I ordered new vacuum hoses and an EGR delete kit so that is another reason I took everything apart.
