90 zr1 no start

[Z51JEFF]

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.

Thats pretty good,you come over here racking everybodys brain,find the problem then keep it so yourself?Next time you have a problem just how many people do you think will be forthcoming to help you out and you will a problem with something.Good luck with that one Newbe.As far as Marc H goes all anybody has to do I give him call,hes more than willing to help an owner out.

[Racinfan83]

Yeah I have to say that I personally think this is a load of ####. He doesn't have to post how much he paid or anything else. And one way or the other - I am still planning on taking my car to Marc - so I don't care. But the whole idea of a forum is to HELP EACH OTHER OUT - and after we all did research and racked our brains thinking of solutions to help the guy (and the tech) fix the issue - the LEAST he could do is tell us WHAT WAS WRONG WITH IT!!!!

[Marc Haibeck]

Hi All,

Here’s a summary of how we fixed Pat’s engine.

The ECM was dead. It would not even pass the power-up self-test. In this state it can’t send fuel injector pulses. We installed a good ECM and the engine started.

There was a misfire and a thick stream of white smoke in the exhaust. We found that the switched wire for the number one primary fuel injector was pinched under the plenum. This causes the injector to run wide open whenever the ignition switch is on. The wire was freed and repaired. At this point the engine ran smoothly.

There was little activity from the left oxygen sensor. The stream of liquid fuel probably damaged it. The sensor was replaced and operation of the engine seemed normal.

Finally, we removed the plenum to repair three vacuum lines that were in poor physical condition. We normally test the operation of the secondary port throttles when the plenum is off. The ignition is turned on and then ECM pin C17 is grounded. The left bank port throttles would open only about 20%. Somewhere in the distant past, years ago, someone had removed the cylinder heads. They did not fully tighten the secondary throttle shaft nuts. All four of them were loose. This causes the throttle plates to slip when the actuator arm is moved. We correctly tightened the throttle shaft nuts. I noticed that the engine has about 40 additional hp now that the all of the secondary port throttles open fully.

[Blue Flame Restorations]

Thanks for the explanation of events, Marc. Always nice to hear you walk through things.

Brett!

[Dynomite]

Thanks Marc.....WOW....who would have guessed

Cliff

[Racinfan83]

Thanks Marc! It's always good to know what to look for...

And I am looking forward to bringing mine up there when I get the funds!

[scottfab]

Originally Posted by Marc Haibeck

Hi All,

Here’s a summary of how we fixed Pat’s engine.

The ECM was dead. It would not even pass the power-up self-test. In this state it can’t send fuel injector pulses. We installed a good ECM and the engine started.

There was a misfire and a thick stream of white smoke in the exhaust. We found that the switched wire for the number one primary fuel injector was pinched under the plenum. This causes the injector to run wide open whenever the ignition switch is on. The wire was freed and repaired. At this point the engine ran smoothly.

There was little activity from the left oxygen sensor. The stream of liquid fuel probably damaged it. The sensor was replaced and operation of the engine seemed normal.

Finally, we removed the plenum to repair three vacuum lines that were in poor physical condition. We normally test the operation of the secondary port throttles when the plenum is off. The ignition is turned on and then ECM pin C17 is grounded. The left bank port throttles would open only about 20%. Somewhere in the distant past, years ago, someone had removed the cylinder heads. They did not fully tighten the secondary throttle shaft nuts. All four of them were loose. This causes the throttle plates to slip when the actuator arm is moved. We correctly tightened the throttle shaft nuts. I noticed that the engine has about 40 additional hp now that the all of the secondary port throttles open fully.

See it's stuff like this that builds trust and confidence such that why would you take your car to anyone else when the time comes?