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please help!

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Old 04-07-2013, 07:07 PM
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I just bought a new crate engine from S&J engines. I just tried to start it for the first time and it idles ok but above 1k it sounds like it is missing or the firing is out of order. It will only idle for about 10sec before it dies. If you try and keep it running it sounds horrid. I have checked and rechecked the firing order and plug wires. I am still a novice trying to afford to do this by doing it myself. I do not know what would cause this. Everything is plugged in it looks like everything is setup the way it should be I dont know what to do.
Old 04-07-2013, 07:09 PM
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Check CPS I bumped mine while doing my motor swap , Idk I'd check that first mainly bc I had simptoms as u are
Old 04-07-2013, 07:17 PM
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How can i check it? is there a resistance across the wires? is it something i can hook a multi-meter up to and test?
Old 04-07-2013, 07:20 PM
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I've never checked w muilti meter I'm sure there is a way, is check wires going to it in the harness then also check sensor itself mine I had bent / tweaked to get me by few days Idk that this is ur problem or not but good starting point imo
Old 04-07-2013, 07:36 PM
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A bad CPS won't cause a bad idle or a miss. But, It will cause a no start or random shutdowns. You need to start by checking if you have a good strong BLUE spark also check you fuel pressure at the fuel rail with a mechanical pressure gauge. Those are a couple of things you should start checking before you start throwing parts at it.
Old 04-07-2013, 07:40 PM
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thank you for the input. what psi should the fuel rail be?
Old 04-07-2013, 08:06 PM
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Originally Posted by Mcwille117
thank you for the input. what psi should the fuel rail be?
It depends on what year yours is I know that mine is 49psi but mine is a 98. I think older models are somewhere around 35 psi +or- 5psi. But I don't remember what year the pressures changed.

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