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Strange No Start Problem

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Old 06-22-2013, 04:19 PM
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Default Strange No Start Problem

Ill try to keep this short. Basically I pulled my 98 Z28 out of storage and it wouldn't start. Spark was good, fuel pressure was gone. Started right up on starting fluid. Towed it home, and it would no longer start with spray but it would backfire out of the airbox.
I replaced the fuel pump and and drained all the gas. Replaced the fuel filter and it still no starts. Threw in a fresh battery and starter, still don't start. Replaced plugs, still nothing. Replaced temp sensor, crank position sensor, and throttle position sensor, still nothing. Live data scan only showed low voltage to TPS, that's why I replaced it. Noid light shows no injector pulse with or without all injectors plugged in. I'm at a loss.
Old 06-22-2013, 04:51 PM
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Wow... holy parts fest batman.

So you now have good fuel pressure, it just still won't start? Have you checked compression/timing?
Old 06-22-2013, 05:31 PM
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I know, I've been chasing my tail here. I don't have the tools to do compression test. Really don't want to pay to have it towed again. Fuel pressure is 55lbs on the rail. Just checked all my injector harnesses with test light. They all have power with the key on. Both injector fuses are good. Don't know what else I can do that's not gonna break the bank.
Old 06-22-2013, 05:56 PM
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You can rent one from Autozone or similar places. The fact that it wouldn't run again on the starting fluid, and the backfire through the intake makes me think you've either lost the timing chain or jumped it. A compression check will tell you if your timing is off such that it won't make enough pressure to fire.
Old 06-23-2013, 04:38 PM
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Does my fuel pressure need to be North of 55, or is that enough?
Old 06-23-2013, 05:00 PM
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GMHTP says 58psi minimum. That may be within the accuracy of the gauge you are using. Also, if you have 55 it should at least TRY to start, 3 psi will NOT make enough difference that it won't run, just won't be as efficient as it could be/will run leaner.
Old 06-29-2013, 10:11 PM
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Should I try to rent tools to do a compression test, or would it be easier to remove a valve cover to see if the TC jumped or broke?
Old 06-30-2013, 12:06 AM
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Originally Posted by 1998Z28LOADED
Should I try to rent tools to do a compression test, or would it be easier to remove a valve cover to see if the TC jumped or broke?
Whichever seems easiest to you. The valve cover might be tricky because if it just "jumped" time, then you will still see valve movement it just won't be when the engine needs it.



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