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tune-up trouble

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Old Jun 21, 2006 | 11:00 AM
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Default tune-up trouble

I have a 91 with a vin 8. Installed new plugs,wires, cap and rotor. It ran ok before, just lacked power. It has high miles at 155. Now it is sometimes hard starting, especially when cold, idles rough intermittedly, almost stalled idling in drive yesterday. Didn't check timing after installing parts, could that be most of my trouble? I have checked my wire connections and routing and it looks fine. Any Ideas from any of you out there would be greatly appreciated!!! Thanks, Jay
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Old Jun 21, 2006 | 11:08 AM
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Are the injectors fairly new or have you done a leak down/pressure test on them? Do you have spark when the engine is initally cranked?
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Old Jun 21, 2006 | 02:34 PM
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Any codes?
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Old Jun 21, 2006 | 03:09 PM
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Do you have a timing light? Check for intermittent spark on all the wires during cold idle. The new wires are sometimes crap out of the box (especially if you crimp em yourself.:bb )

Also you should run through the idle setting procedure, clean out the Idle Controller and throttlebody as part of normal maintenance.
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Old Jun 21, 2006 | 03:11 PM
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I have owned the car less than a year but was told that they were replaced three years ago. I did have a mechanic replace the fuel filter while I watched. It was on very tight and was difficult to thread on new one. Threads didn't look so good and someone had put some kind of thread material like locktite or something and my mechanic could not clean it off since it had hardened. He also didn't check for leaks after the installation. This occurred a few days prior to my tune up and everything seemed ok before my tune-up. Thanks for your input, Jay
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Old Jun 21, 2006 | 03:12 PM
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no codes
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Old Jun 21, 2006 | 03:19 PM
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thanks for the info. The wire set is new, genuine GM set so no crimping was done. I will clean the throttle body though since I have not done that yet. thanks!!
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Old Jun 21, 2006 | 03:32 PM
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None of those items should affect the car in the way you had stated. Is it possible that the rotor/cap are not on properly. Did you place the insulator on the cap properly? Are any of the plug wires touching the exhaust manifold?

Good luck,
Dino
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Old Jun 21, 2006 | 03:36 PM
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This is a long shot, always check the last place you were. Check the spring and button in the center of the cap to make sure it is properly installed in the correct order and looks OK.
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Old Jun 21, 2006 | 05:38 PM
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Yes Dino, I did discover two of the plug wires touching exhaust manifold. I hope I haven't ruined those wires since I have put a hundred miles or so on them. Thanks, I am going to re-route some of the other wires as well. The old ones were put on wrong with broken holders so it was hard to figure out where they were supposed to go. Thanks for your help Dino!!!!!! Jay
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Old Jun 21, 2006 | 05:41 PM
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Good idea, I will check that as well. The plug wires touching the exhaust manifold may have been tdhe cause of my problems, thanks, Jay
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