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Injector swap now rough idle.

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Old 01-19-2014, 08:27 PM
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Default Injector swap now rough idle.

I swapped in re conditioned 703s into my 1991 laredo. All resistances of injectors were between 13.2 -13.6 . I tried the re flashing sequence and also drove it around for 20 minutes to see if that would make it level out. What i've noticed is that when I unplug #1 injector it makes no difference on how the engine runs, I can also unplug #1 spark plug and it makes no difference. I checked for spark on #1 and there is definetly spark. I never had a no fire problem before swapping in the injectors.. Could I be missing something simple?

Thanks
Old 01-19-2014, 08:32 PM
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the simple thing is a bad injector... or issue with an injector.. on #1...

my question is... did you plug the injectors back up with their corresponding connector??
Old 01-19-2014, 08:35 PM
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I had to reset my PCM twice before it actually properly reset. Mine was running all sorts of crazy, CEL was on for a slow MAP sensor or something.

I basically disconnected the + terminal from the battery, re-checked that all my connectors were tight and in the right order, then reset the PCM by touching the positive battery cable to the negative terminal/cable for a full minute or more. Hooked everything back up and did the ignition on - headlights on/off - ignition off sequence and it started right up beautifully.

The first time I started it after that, it fired so quickly that it startled me

If not, you might have a bad injector? If there is spark on cyl 1, and disconnecting the spark on that cyl yeilds no change in how it runs, than you can assume you isolated the problem area. Maybe try to cycle the injector manually out of the car and make sure it cycles properly.
Old 01-19-2014, 08:40 PM
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#1 and #2 are connected at the harness right next to each other... im betting you might have crossed them!
Old 01-19-2014, 09:01 PM
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I labeled the injector wires as I pulled them off but I guess there is always a chance that I could have mixed it up somehow. I will go try swapping them and resetting ecm again and report back
Old 01-19-2014, 09:06 PM
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i didnt know you labeled them... i was in a rush and just kind of folded them back in order.. hmm.. now im back to faulty injector
Old 01-19-2014, 09:19 PM
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If they were crossed you wold have two dead cyls , try tapping on injector with small screw driver yet ?
Old 01-19-2014, 09:22 PM
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did he check cylinder 2? i just thought he checked #1 because of his post
Old 01-19-2014, 09:27 PM
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tried swapping them and it made no noticeable difference. Also should mention that the #2 injector plug wires had pushed into the plastic clip far enough that they would no longer connect, I took off the rubber seal and pushed them back in and made sure it has contact with male ends in injector.

This is how my wires look right now for #1 and #2 .. is this right?

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Old 01-19-2014, 09:29 PM
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Originally Posted by freegdr
If they were crossed you wold have two dead cyls , try tapping on injector with small screw driver yet ?
What does that do?
Old 01-19-2014, 09:29 PM
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Originally Posted by JackJare9455
did he check cylinder 2? i just thought he checked #1 because of his post

I notice a difference in idle when #2 injector is unplugged while running.
Old 01-19-2014, 09:31 PM
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Originally Posted by bikerboyriley
I notice a difference in idle when #2 injector is unplugged while running.
Try tapping injector might be stuck they do get stuck if fuel has dried up inside them.
Old 01-19-2014, 09:32 PM
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weird.. our number two wires are backwards when i compare them.. my tan.. or whatever color that is... faces towards the inside.. hmm..
Old 01-19-2014, 09:33 PM
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Originally Posted by bikerboyriley
tried swapping them and it made no noticeable difference. Also should mention that the #2 injector plug wires had pushed into the plastic clip far enough that they would no longer connect, I took off the rubber seal and pushed them back in and made sure it has contact with male ends in injector.

This is how my wires look right now for #1 and #2 .. is this right?

They should lay were they were pluged in from being in same place since 91...
Old 01-19-2014, 09:35 PM
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Originally Posted by JackJare9455
weird.. our number two wires are backwards when i compare them.. my tan.. or whatever color that is... faces towards the inside.. hmm..

Ive tried swapping them both ways, doesnt seem to make a difference.... But if yours is the other way then that would be the correct way and I will put mine back that way.


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