90 zr1 no start

[Racinfan83]

I'm new to these cars but have some mechanical knowledge. And I'm just gonna throw this out there - as I have had a couple vehicles in the past that had an intermittent no start problem - and the switch was bad. Anybody try changing out the actual ignition switch?

[Dynomite]

Originally Posted by Racinfan83

I'm new to these cars but have some mechanical knowledge. And I'm just gonna throw this out there - as I have had a couple vehicles in the past that had an intermittent no start problem - and the switch was bad. Anybody try changing out the actual ignition switch?

Tom refers to a wire in the Ignition Key Cylinder goes bad

zr1don has replaced the Ignition Key Lock Cylinder in his 90 ZR1

[scottfab]

A few things come to mind before shot gunning components and systems. That you may get lucky with it but this can be very expensive a even more frustrating than what's happened up to now.

The key to me would seem to be in data collection. If you can't find what it IS then find out what it is NOT.

Start over. Assume almost nothing.
Since it has been reported that it "runs on carb cleaner" then fuel seems to be the issue.
(this should completely eliminate the ignition: key, ignition, clutch switch etc)
So now then, if there is adequate fuel pressure at the rail (>40psi) then one would think injectors are not getting told to open. One thing we can assume is that whatever the issue is in the electronics (that which speaks to the injectors) it's intermittent.

The enemy of intermittent issues is data collection.
So now then, here is where you (or whomever) has to toss the FSM troubleshooting tree and think outside the box. Data about the injector circuit has the be collected. This will mean instrumenting such that this data can be seen. The best place has to be right there on one of the injectors. An easy mistake to make would be to use a chassis ground instead of the wires right on the injector (any injector). Another mistake would be to use data collected from the ECM (via a datalogger) because even if the system is demanding fuel it does not mean the injectors are getting the word.
The best way I know of to get the data right at the injector is with an oscilloscope.

So there you have it. Put a scope on an injector when the "no-start" happens while cranking. Even if the thing starts while you have the injector on the scope this data can be useful. It will show what the drive electronics looks like when working. This then can be used to compare to what it looks like during a no-start.

If the signal goes away at the injector you're almost home.

Whoever gets the task at finding this issue has to be determined, focused and pertinacious. Like a dog with a bone one has to resolve to find the SOB.

After 40yrs of such kind of work in electronics and software I can tell you that not all faults can be effectively found following a "service manual". Sometimes critical thinking is required.
May the force be with you

[MEANDMYZR1]

Hello everyone. I wanted to get back to this. It took a while to get my car up to Chicago where Marc Haibeck fixed it in one morning. Then, he had to fix the other stuff the dealership put back together wrong. If I ever have a problem again, I'm not going to waste my time with anything else, I'm just sending it directly to him. He was awesome to work with and now my car is better than it has been in ten years. For all the others that emailed me to send it to him, thank you.

[Dynomite]

Originally Posted by MEANDMYZR1

Hello everyone. I wanted to get back to this. It took a while to get my car up to Chicago where Marc Haibeck fixed it in one morning. Then, he had to fix the other stuff the dealership put back together wrong. If I ever have a problem again, I'm not going to waste my time with anything else, I'm just sending it directly to him. He was awesome to work with and now my car is better than it has been in ten years. For all the others that emailed me to send it to him, thank you.

Soooooo.....what did Marc do?

Or.......

Marc.....what was wrong and how did you fix it?
And......what stuff did the dealership put together wrong?

[Racinfan83]

No doubt! After following this thread since the beginning I would love to know what was wrong with it!
And I'm gonna take mine to Marc as soon as I get the dollars together...fo
shore

[MEANDMYZR1]

I elected not to say what was wrong with it because in the end I didn't have to pay Marc that much to fix it. So, I thought I would just let people send him more cars, so he can make some money, and continues to help us all like that.

[Dynomite]

Originally Posted by MEANDMYZR1

I elected not to say what was wrong with it because in the end I didn't have to pay Marc that much to fix it. So, I thought I would just let people send him more cars, so he can make some money, and continues to help us all like that.

Good answere

I understand that but I will now keep guessing. I will not ask Marc about technical issues of others for exactly the reasons you describe.....but I thought it was worth a try just once

Marc is definitely a super help on ALL technical issues
Haibeck Automotive Technology

[scottfab]

Originally Posted by MEANDMYZR1

I elected not to say what was wrong with it because in the end I didn't have to pay Marc that much to fix it. So, I thought I would just let people send him more cars, so he can make some money, and continues to help us all like that.

Interesting.

[WVZR-1]

Originally Posted by MEANDMYZR1

I elected not to say what was wrong with it because in the end I didn't have to pay Marc that much to fix it. So, I thought I would just let people send him more cars, so he can make some money, and continues to help us all like that.

I can't say that I understand that approach - most aren't "in the neighborhood" and some aren't even in the country! Quite a "contribution" you've made to the "hobby"!!