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Hi, I’m Ron and I can help you.I have been in the auto repair business with my own shops since 1975 and also teach automotive repair. I am confident we can resolve your problem together. Please understand that I don't know your skill level. In most cases when you have a problem with the way the vehicle performs, specialized tooling is required to acquire computer data/information or engine testing results. We didn’t build these complicated vehicles; we just diagnose and fix them. Also understand that I can't see, smell, hear, or touch the vehicle either, so it may take a few replies to get to satisfactory results. I am also going to direct you with the fastest, easiest and most common things to check first. Please be patient and permit me to do what I do best.I also try to give all of the information you may need, expecting a “positive rating” in return. I will also continue assisting you after you have rated me, if necessary. If there is any reason I cannot get a positive rating, please let me know why “in advance”, so I can go another direction for you. I am sorry you’re having this problem; I’ll help you through it.
Something is wrong with the timing of the reluctor wheel and the CRANK sensor, this is why it runs when you disconnect it, it is sending an incorrect signal to the computer when it's connected.
Okay, then it's possible we have slipped timing belt/chain.
Either that, or the PCM can be bad, BUT I would run some tests with the scan tool at this point, running and KOEO.
Thanks again, and please don't forget to rate me and keep this link in case you need me again later on.
I've heard this complaint many times, and it's always been a timing issue. something has to have slipped out of time somewhere. Wish I was there to help you, we'd find it.
I'll opt out for you. Thanks, Ron
You need to plug everything in and clear the codes with a scan tool. Try to start it and see which code comes up. You need a scan tool to make sure you have cam to crank sensor correlation.
Do you have a scan tool capable of reading live data?
Check to see if you are getting an rpm signal on the scan tool while cranking engine.
Sounds like you may have an intermittent wiring issue. Check connectors at crank sensor and pcm look for corrosion. Look for any broken or pinched wiring. You may have to hook this up to an oscilloscope to find the problem.
You need to look in the scan tool and see if you have a cam to crank sensor correlation, it should say yes or no.
If you can unplug one sensor and it runs, they are out of sync, the ecm will prevent the engine from starting. This is a safety feature in the ecm to prevent valve damage. if the timing is actually off.
it used pulse width to determine the crank position and compares it to cam pulse signal. if they are out of sync it will not start. I would double check that reluctor on the crank shaft. I would not listen to those sites, it definately has a key way and matters about the indexing.
if you unplug ckp and it runs good, no misfires, then your mechanical valve timing should be ok, when you unplug the ckp the ecm uses a base timing value to fire the coils.
if you plug in ckp and engine stalls, the correlation in off, then your reluctors on the cam or crank are off.
I don't think you can bypass, you need those ckp and cmp values in the ecm for it to run properly.