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1 minute ago, Jeep Driver said:

Yes,  you'll have a TPS  or throttle position sensor. 

would that have anything to do with the no start problem?

 

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Let's keep this simple. 

 

TBI, ECU will prime fuel pump for 2-3 seconds when you turn the key to on or ignition. After it primes it will shut the pump off. 

 

ECU, when ECU senses that the engine is turning over, signal from CPS, it will run the pump and send a pulse signal to the injector and allow spark. 

 

CPS, if no signal to ECU, ECU will shut down pump and end pulse signal to injector and end spark. 

 

If your injector is not pulsating- no signal from CPS to ECU. Or you have a wiring issue or you have a bad ECU. 

 

 

It's that simple. 

 

What ECU did you get to replace the original and why did you replace it?

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Right now, I've got this Comanche that a man is trying to get running for his son as a first vehicle. He's in way over his head in the amount of money he's spent on this thing. In addition to that I've got a 99 Chevy Suburban with a 5.7L vortec that is pushing antifreeze into the crankcase and a 96 Ford explorer that is throwing O2 sensor codes after replacing the exhaust system and a 77 Jeep CJ7 complete rebuild project going on all at the same time! I'm stretched a little thin at the moment. 

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3 minutes ago, Jeep Driver said:

Let's keep this simple. 

 

TBI, ECU will prime fuel pump for 2-3 seconds when you turn the key to on or ignition. After it primes it will shut the pump off. 

 

ECU, when ECU senses that the engine is turning over, signal from CPS, it will run the pump and send a pulse signal to the injector and allow spark. 

 

CPS, if no signal to ECU, ECU will shut down pump and end pulse signal to injector and end spark. 

 

If your injector is not pulsating- no signal from CPS to ECU. Or you have a wiring issue or you have a bad ECU. 

 

 

It's that simple. 

 

What ECU did you get to replace the original and why did you replace it?

YES!!!! This is what I needed!!! Thank You!!! Ok... I think we can go from here. Jeep Driver, YOU ARE THE MAN!!!! CPS or wiring issues. Thank you! 

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13 minutes ago, Jeep Driver said:

Let's keep this simple. 

 

TBI, ECU will prime fuel pump for 2-3 seconds when you turn the key to on or ignition. After it primes it will shut the pump off. 

 

ECU, when ECU senses that the engine is turning over, signal from CPS, it will run the pump and send a pulse signal to the injector and allow spark. 

 

CPS, if no signal to ECU, ECU will shut down pump and end pulse signal to injector and end spark. 

 

If your injector is not pulsating- no signal from CPS to ECU. Or you have a wiring issue or you have a bad ECU. 

 

 

It's that simple. 

 

 

Well said.

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1 hour ago, wclegere said:

Engine has plenty of spark. Yes it will fire when gas is dumped into the TB but that really doesn't help much with the solution, does it? 

 

Of course it helps.

 

An internal combustion engine needs three things to start and run: fuel, air, and spark. If all you know is that it won't start, you don't know what to check first. If you can pour gas into the throttle body and it starts, that verifies that the ignition system isn't a problem. So you DON'T worry about CPS, ECM, coil, or distributor. Also, it's getting air so you don't worry about valves or camshaft.

 

So you're down to a fuel delivery problem. Focus your attention on troubleshooting the fuel system.

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