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  #13  
Old 07-17-2016, 12:27 PM
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Re: Rough Idle & Stumbling

I picked up a cheap can of carb cleaner and checked all the vacuum lines, base of the throttle body and intake gasket. Idle never changed so I removed the breather hose from the throttle body cover and sprayed into the cover to see if the cheap stuff would cause an idle change. What that did was the smooth out the engine and that lasted a few minutes until the vibration returned but less than before. From that it suggests to me the problem lies in one or more of the injector(s) since the carb cleaner basically added fuel to all the cylinders. I put some Lucas cleaner in the tank and filled it up once again. When the problem arose I had put in the Lucas cleaner but added too much gas. That did seem to help it a little so I'm going to run it a few days and see if it clears up.
Thanks for all your help and I'll let you know how it's going in a few days...

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  #14  
Old 07-18-2016, 08:21 PM
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Re: Rough Idle & Stumbling

It's still a bit rough and got a code for the 5th spark plug and then later on today while on the highway a lean code came up. I picked up a fuel rail with the injectors from a good running Jeep and a new coil pack for the price I could not turn down. The plugs on a couple of injectors are broken so I'll pick up another harness. I've been trying to find where that harness connects to but I can't find it. Can anyone show me a drawing or a picture where the connection is. I could cut the bad plugs off and wire in some good plugs but I'm concerned about building up resistance in the wires.
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  #15  
Old 07-18-2016, 10:52 PM
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Re: Rough Idle & Stumbling

Hmm, did you get a misfire code for the #5 plug? And a lean code now as well. Do you have a scanner with live data? Would be good to check your fuel trim figures. Eventhough i told before that the filter/pressure regulator should not be the problem, these new events could point towards a (too) low fuel pressure. With a too low pressure, the PCM will compensate with a possitive fuel trim, until +25 i believe, and then it will set a lean code. If the mixture becomes too lean, it can start causing misfires.
Also a bad O2 sensor can be your problem. If it sees a lean mixture, while it is not, it will add more fuel and finally show the lean code.
So i would first check the fuel trims and the O2 sensor readings. The O2 sensor(s) 1-1 (and 2-1 if you have 4 sensors) should fluctuate between 0.2 and 0.8V.
If you have a fuel pressure tester, then you can also check the fuel pressure itself, which should be around the 45 psi.
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  #16  
Old 07-19-2016, 06:51 PM
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Re: Rough Idle & Stumbling

Fixed, I changed the fuel rail and injectors and it's nice and smooth along with more power. I'm not a paranoid freak but I'm thinking some guy who lives very close to where I park my cars put something in the gas which damaged one or more injectors. He has played some games with my Pontiac and this problem with the Jeep happened overnight. I parked the Jeep one evening , took my Pontiac out for a cruise and then parked the Pontiac the next day and drove my Jeep home. I had the Jeep running for about 15 minutes and then the miss started. I can't do anything until I catch the ahole but I will one day if he continues. For now it's locking gas caps.
Thanks for all your help....
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