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Discussion Starter #1
Kinda puzzled why #1 and 8 cylinders don't work. This is a swap into a CJ using a 98 vortec 350 w/ 97 computer. All input welcome. :D
 

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I can't remember if that is port injection or TBI. If it is TBI it has to be a spark issue. Did you remember to check the basics. Cap, rotor, wotes, plugs, etc. If it is port injection, it could be spark or fuel. Is compression ok? You could have clogged injectors or they could just be dead. I know they can be tested with an ohm meter, but I don't know what the numbers are supposed to be. Maybe you can check the reststance across the injectors on the good cylinders and see if the bad ones are the same. I can't remember if the engine has to be running or just power on. I would try it with just power on first. I don't know why this would matter, but is the fuel rail inlet at #1 and the return at #8? Could it be some goofy pressure problem? I hope I gave you some ideas here. Good luck.
 

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motorhead72k5 said:
I can't remember if that is port injection or TBI. If it is TBI it has to be a spark issue.
It is a Vortec MPI engine. TBI injection wouldn't have a #1 or 8 injector.


My first thought would be is the 97 computer from a V8 or V6????????????
 

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Discussion Starter #4
I tried 2 computers with the same result. I'm almost sure they were both V8's. It's looking like a couple clogged injectors. The motor had been sitting for at least a year. I dumped some injector cleaner in the tank, but I don't have much faith in that kind of crap!
 

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Check the wiring. 90% of EFI related problems I see are from a poor connection.
 

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My friend and I put a 350 TBI in an 81 cruiser and it would not run at all, no combustion whatsoever. All wiring correct, fuel to throttle body, and good spark, no combustion. Spoke with the tech guys at Howell EFI where we got the wiring kit from and they said that if the motor was sitting for a while, 6 mo or more, that injectors can freeze closed. They told us to crank the motor while tapping very firmly directly on the injector with a screwdriver handle or something similar. It worked after about 6-8 taps while cranking the motor fired right up, ran rough for about 10-15 seconds and then smoothed right out, had to tap on both injectors. Maybe 1 and 8 are frozen shut on you. Worth a try anyway.
 

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Discussion Starter #7
82TOYLB said:
My friend and I put a 350 TBI in an 81 cruiser and it would not run at all, no combustion whatsoever. All wiring correct, fuel to throttle body, and good spark, no combustion. Spoke with the tech guys at Howell EFI where we got the wiring kit from and they said that if the motor was sitting for a while, 6 mo or more, that injectors can freeze closed. They told us to crank the motor while tapping very firmly directly on the injector with a screwdriver handle or something similar. It worked after about 6-8 taps while cranking the motor fired right up, ran rough for about 10-15 seconds and then smoothed right out, had to tap on both injectors. Maybe 1 and 8 are frozen shut on you. Worth a try anyway.
Yeah, I'm thinking a couple stuck injectors. The Vortec has a composite cover and the injectors are inside. Not sure how I can tap on them. :D
 

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Boggerdust said:


Yeah, I'm thinking a couple stuck injectors. The Vortec has a composite cover and the injectors are inside. Not sure how I can tap on them. :D
i think those injectors have a poppet valve in them that get stuck.i send them into the dealer under warranty. never messed with em myself yet. knocking on wood.
 

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you need to get the pinout for the 97 computer. it is different than your 98's harness. you need to move some wires around. i run a 97 computer with my 99 motor and i had the exact same problem when i first hoked it up. the pins are really easy to move around in the vcm connectors. if you will e-mail me at [email protected] i will send you a copy of the pinout of the 97's vcm connectors.
 

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Discussion Starter #10
High5 said:
you need to get the pinout for the 97 computer. it is different than your 98's harness. you need to move some wires around. i run a 97 computer with my 99 motor and i had the exact same problem when i first hoked it up. the pins are really easy to move around in the vcm connectors. if you will e-mail me at [email protected] i will send you a copy of the pinout of the 97's vcm connectors.
Thats great info! I emailed ya for the '97 pinout!!
 

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Discussion Starter #13
Moved the two wires and it purrs like a kitten.....well maybe just a bit louder than a kitten :D Thanks again High5!!!!!!
 
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