newbie C4 starting problem
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2nd Gear
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newbie C4 starting problem
Hi Folks!
My name is Brian and I'm looking for help for my brother's Corvette. He has an '89 C4 that has a starting issue. Naturally, it is an intermittent problem, but here goes. He will drive the car a few times and all is well. Then he will go somewhere and the car won't start. If he squirts some ether into it, it starts right up. He has checked the filters, and replaced them. The fuel rail has pressure and fuel squirts out of the Schrader valve when actuated. Is there something in the ECM that tells the system to inject a small amount of fuel into the engine for starting, like the old carburetors had? As I said, this is an intermittent problem. It doesn't happen EVERY time, but frequently enough to drive him nuts. Any help is appreciated. Thanks in advance.
Brian
My name is Brian and I'm looking for help for my brother's Corvette. He has an '89 C4 that has a starting issue. Naturally, it is an intermittent problem, but here goes. He will drive the car a few times and all is well. Then he will go somewhere and the car won't start. If he squirts some ether into it, it starts right up. He has checked the filters, and replaced them. The fuel rail has pressure and fuel squirts out of the Schrader valve when actuated. Is there something in the ECM that tells the system to inject a small amount of fuel into the engine for starting, like the old carburetors had? As I said, this is an intermittent problem. It doesn't happen EVERY time, but frequently enough to drive him nuts. Any help is appreciated. Thanks in advance.
Brian
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From: Kingman AZ
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2nd Gear
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Brian
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Joined: Apr 2002
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From: Anaheim CA
There are multiple problems with the "Engine start sequence" document but it will still guide you to what needs to happen to start the engine.
Examples of problems:
There is no oil pressure input to the ECM, so it does not need to see oil pressure to fire the injectors.
All 8 injectors in an L98 are connected together in parallel and they all fire at the same time, once per revolution. The "banks" are not separate and do not fire alternately.
There is no Idle Air Mixture valve, so obviously it can't be "misadjusted". There is an IAC (Idle Air Control), but it is a stepper motor controlled by the ECM and there is no adjustment.
