rough idle caused by electrical system overload
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rough idle caused by electrical system overload
Here is my problem. I have a 1990 F-150XLT 4x4 with the 4.9l. The other day I stopped to help a guy stuck in the middle of the road (first mistake), long story short, he tried to jump his car off of my truck while it was running. He hooked up the cables backwards before I could get out of the truck to stop him, at the same time his buddy hit the ignition in his car and mine died.
So.. I have replaced the battery, a wiring harness from the stater relay to the alternator, the fuel pump relay and also cleaned out the throttle body. It is not putting out any codes, however it starts and idles extremely rough. Once the truck is moving it accelerates and drives smoothly.
My question is, what else could it be? I am clueless where to start without having any codes to go by. I'm assuming that it could be a MAP sensor, or the Idle Control sensor or maybe even the brain. Any suggestions? I'm already $400 into this fiasco and I'd rather not start pupming parts into it until I have an idea where I should start.
Thanks,
keith
So.. I have replaced the battery, a wiring harness from the stater relay to the alternator, the fuel pump relay and also cleaned out the throttle body. It is not putting out any codes, however it starts and idles extremely rough. Once the truck is moving it accelerates and drives smoothly.
My question is, what else could it be? I am clueless where to start without having any codes to go by. I'm assuming that it could be a MAP sensor, or the Idle Control sensor or maybe even the brain. Any suggestions? I'm already $400 into this fiasco and I'd rather not start pupming parts into it until I have an idea where I should start.
Thanks,
keith
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rough idle caused by electrical system overload
I would try to generate a code by unhooking the TPS and driving it until the check engine light comes on or several miles. If it never sets a code I would then assume the ECM may be damaged.
2000 XLT Flare Supercab Sport 5.4-Auto-355LS-Tow pkg-Bedrug-Xtang Tonneau
2000 XLT Flare Supercab Sport 5.4-Auto-355LS-Tow pkg-Bedrug-Xtang Tonneau
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From: South East Alabama
rough idle caused by electrical system overload
KDB,
You might try disconnecting the battery for fifteen minutes to clear the computer. Start from scratch and see if your truck can relearn the parameters of smooth idle. This might take several start,warm-up,run cycles.
shotgun
You might try disconnecting the battery for fifteen minutes to clear the computer. Start from scratch and see if your truck can relearn the parameters of smooth idle. This might take several start,warm-up,run cycles.
shotgun
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rough idle caused by electrical system overload
Thanks for the help, I also forgot to mention that the tachometer acts weird. It jumps randomly while idling and appears to function normally while driving. Also I noticed last night that the Check Engine light is glowing faintly. Perhaps it is giving code now.
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d_stange
1987 - 1996 F150 & Larger F-Series Trucks
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Jun 21, 2006 06:41 AM
