1991 460 rough/missing idle!?
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1991 460 rough/missing idle!?
So I have a 91 F250 7.5 105k and it was running great when I took it in to get the exhaust and cat delete done. I drove it home about 20 miles after the exhaust install and even dove it another 30 miles to my A/C guys house, but on the way to my A/C guys house it started to miss under light acceleration and the more I drove it the idle would get worse. So luckily I lip her all the way home, another 30 miles on back streets, sometimes having to feather the throttle at stop lights or it would die sometimes. Fast forward to this week and I cleaned the IAC and replaced the fuel pressure regulator. Those two things seemed to help and it seems to run great when cold, but when it heats up it starts to idle rough! Any help would be greatly appreciated!
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Cross-Country
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I did pickup a MAP sensor also, but really not looking to just start throwing parts at it in hopes of fixing. I am off tomorrow and hoping to spend sometime trying to figure the problem out, so any info would be great!
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From: Houston/Sugar Land
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Anyone have ideas? It starts up great, but idles rough and pretty bad stutter/mis under light acceleration. When you really get on it, it seems to somewhat clear up but when you let off the throttle it gets rough again!
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That doesn’t mean there aren’t fault codes present. Run the KOEO self test. Check fuel pressure with a gauge connected to the schrader valve on the fuel rail.
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Ok, I will be picking up a fuel pressure tester today and checking KOEO.
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