Another misfire question

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Feb 20, 2012 | 07:41 PM

bucks150

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Another misfire question

I've been battling this for awhile. My 91 F150 4x4 5.0 E4OD has a slight miss at idle and at other rpm ranges. I have all new ignition system plugs wires coil ect . I have 38 psi fuel pressure on both tanks. I have replaced the following: vacum lines, fuel filter, front fuel tank with new pump, IAC, TPS, ECT, ACT, EGR valve solenoid ,and the O2 sensor. The only thing that hasn't been replaced is the EGR valve, EGR valve position sensor, and the purge canister solenoid. The EGR valve has been cleaned and is in working order. I have checked for codes. The only codes that I got was 111 KOEO & KOER. What else would cause this? All input will be appreciated.
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Feb 21, 2012 | 08:19 AM

Prof2113

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Try a leakdown test just to confirm that you don't have a burned valve. I had two on my '96 300 I6. Compression test was fine, didn't show up until the leakdown. Same kinda symptoms. May not be the problem, but if you can rule it out, that's one less thing.

Feb 21, 2012 | 08:25 AM

bucks150

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I would hope that an rebuilt engine with around 50k wouldn't have a burnt valve. When it quits raining and wind blowing like hell ill test and confirm or rule out

Feb 21, 2012 | 08:28 AM

colescoconutz

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From: Crestview

You changed a lot of parts but have you checked timing?

Feb 21, 2012 | 11:59 PM

bucks150

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Done timing bump set at 16° btdc

Feb 22, 2012 | 11:15 AM

bucks150

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I ordered an injector service kit off old fuel injection. com going to service my injectors to see if that will help they are 21 years old I don't think it will hurt.

Feb 23, 2012 | 03:52 PM

rla2005

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From: Kentucky

Check the plug wire routing. Be sure to keep wires for 1&3 and 5&6 away from each other. Here is a photo for the proper plug wire routing on your '91: Steve83 plug wire routing | SuperMotors.net