Bad miss, no codes
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Joined: Aug 2009
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Bad miss, no codes
Hi folks,
I have a 2002 F-150 Supercrew with a 5.4L Triton and she has 94350 miles. Never had a problem until a couple of months ago. The truck acted as is the transmission was slipping, but it wasn't a trans problem. I took it to my mechanic, and he said he could not get any codes to show up even though he felt the lag when he would make a turn, go up a hill, etc. He said it might be the catalytic converter going bad, but wasn't sure. He changed out a vacuum line and it ran much better. He also said if the cat was going out, it would be easier to tell when it finally just laid down and died. The truck ran fine until about 2 weeks ago. I was traveling down the freeway, and it started running "washboard" rough. Felt like I was going down a bad gravel road, then suddenly the SES light came on. It would burn steady, then flash for a few minutes, then back to steady. I took it to my mechanic again. He put it on the computer and got a reading that the number 6 coil pak did not even exist. After a few more tests he ordered a new computer module. When the computer came in, he drove the truck to the Ford dealership (where he used to work) to get the computer programmed. The truck ran perfectly without a single miss. He did not put the new computer in. He put the truck back on the diagnostic computer again, no errors. He even pulled hoses, etc, trying to get an error and never did get one. He told me that he had absolutely no idea what was wrong with the truck. I got in to drive it home, and a few miles down the road, it started the "missing" again. No SES, but it still is running rough. Coil boots are still soft, and one thing that is throwing us off is the fact that the SES light won't come on, even when my tech unplugs things that should make the light come on. The light comes on when you turn on the truck, but while it is missing so bad, no light appears.
My next stop will be the Ford dealership, but I know it will be big $$$. Does anyone have any idea what could be wrong.
I have a 2002 F-150 Supercrew with a 5.4L Triton and she has 94350 miles. Never had a problem until a couple of months ago. The truck acted as is the transmission was slipping, but it wasn't a trans problem. I took it to my mechanic, and he said he could not get any codes to show up even though he felt the lag when he would make a turn, go up a hill, etc. He said it might be the catalytic converter going bad, but wasn't sure. He changed out a vacuum line and it ran much better. He also said if the cat was going out, it would be easier to tell when it finally just laid down and died. The truck ran fine until about 2 weeks ago. I was traveling down the freeway, and it started running "washboard" rough. Felt like I was going down a bad gravel road, then suddenly the SES light came on. It would burn steady, then flash for a few minutes, then back to steady. I took it to my mechanic again. He put it on the computer and got a reading that the number 6 coil pak did not even exist. After a few more tests he ordered a new computer module. When the computer came in, he drove the truck to the Ford dealership (where he used to work) to get the computer programmed. The truck ran perfectly without a single miss. He did not put the new computer in. He put the truck back on the diagnostic computer again, no errors. He even pulled hoses, etc, trying to get an error and never did get one. He told me that he had absolutely no idea what was wrong with the truck. I got in to drive it home, and a few miles down the road, it started the "missing" again. No SES, but it still is running rough. Coil boots are still soft, and one thing that is throwing us off is the fact that the SES light won't come on, even when my tech unplugs things that should make the light come on. The light comes on when you turn on the truck, but while it is missing so bad, no light appears.
My next stop will be the Ford dealership, but I know it will be big $$$. Does anyone have any idea what could be wrong.
