99 exp. rough runner

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Oct 17, 2007 | 11:12 PM

pstork

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99 exp. rough runner

1999 Exp. 5.4L 90,000 miles. Runs rough like it is missing at idle and throughout driving range. I am not getting any codes. Was really bad at first I took out all of my coil over plugs and ohmed them out the primary side of them where all good and the secondary side I had one that was 2500 ohm's hirer so I replaced that one, while I was at it I replaced all of my plugs with motorcraft and took it for a test drive seemed to help but still felt the problem, I also bought a fuel filter but wanted to see if that was the fix before I went on, so I replaced the fuel filter next still not the fix. I checked out the post's and found that my pcv valve and boots on my ecm side could be the problem found that they had deterated and colapsed so I replaced the hose cluster took it for a spin, Still had the problem. I thought taking it for an extened drive I could get a code but still nothing. Where do I go next????????????

Oct 18, 2007 | 09:57 AM

buzzard

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From: All over Texas

pstork, you've nailed the most common culprits so going on from here could be a little tricky, especially without a code. Hopefully someone will come along who has had a similar scenario.

Oct 18, 2007 | 10:17 AM

dr cabela

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since its easy to do u might want to take the EGR valve off and clean the egr valve and clean out the DPFE sensor hose outputs also check the hoses themselves
mine was full of gunk

also carefully check any and all vacuum connections
good start w/ the PVC valve elbow....mine was bad too

found 2 other BAD vacuum leaks when cleaning the DPFE and EGR out cause i could finally see them w/ the black cowling off....easy fix

Oct 18, 2007 | 03:25 PM

pstork

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I did check my egr valve seems to be operating normally and did not appear to have a carbon built up problem. I have an appointment tommorow to have a diagnostic done on it to pin-point the problem area. Then I will have a better idea where to go next. I did check replace the cluster of hoses and elbows off of the pvc valve they had issues. No change in the problem. I checked the DPFE for voltage and ohmed it out checked good. We will see after tommorow what they determane

Oct 18, 2007 | 05:41 PM

fitzy67

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rough running EXP

I have had similar problems many times. The first time was because of leaks in the ciramic tubing serving the EGR valve. These may cost 20 bucks at the dealer. Mine went bad around 90,000 miles. Easy to fix though. Look for the two black tubes that connect to the EGR control and down to two metal lines on the drivers side of the engine. Another thought is have you recently used a pressure washer under the hood? Could have gotten H20 in the Air intake. Take it apart if this is the case and wipe out with a dry rag. let me know if this helps. 2000 EXP 5.4 sprt pkg.

Oct 18, 2007 | 06:37 PM

pstork

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Thanks Fitzy I have not had a powerwasher under the hood and there is no water in the air cleaner but I did look at the boots on the DPFE and they did not appear to be cracked I will have to look at the lines though which have a protective cover on them will get back to ya. I will keep picking away at this thing until it is solved, thanks for everyones input

Oct 18, 2007 | 08:17 PM

ericnj75

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try cleaning the maf.

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Oct 19, 2007 | 11:30 AM

pstork

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well I found the problem had the shop do a diagnostic on it and they found the #8 coil pack bad, they swaped it with #6 and it changed to #6. When I ohmed out that particular one it was like 300 ohms off but not nearly as bad as the one I had replaced, so I put the coil back in that I replaced the first time which was 2600 ohms off and now it runs great. Is that crazy or what so I orderd two more coils one to replace #6 which now has the coil that is way off but working and to have one on hand in the vehicle as a running spare. The dealer is pretty proud of the coil packs they want $90.00 each for them able to get motorcraft through a source for $35 - $40 a piece same ones motorcraft. Hope my troubles helps you with yours and thank everyone for your input.