1991 E4OD problems
I have a 1991 F-150 XLT Lariat (long bed) with a 5.0 and E4OD transmission.
Life story-
The truck has about 112,000 miles on it and was primarily used as a farm truck until I got it at 16. About 4 years ago, it began having what seemed like transmission problems. Unfortunately, I was unable to do anything due to joining the Army and having to let it sit for 3 years while I was in Hawaii. I’m stationed back closer to it now (300 miles), and would like to get it going again as I had very fond memories of this truck and it’s been in the family since leaving the dealership.
The Problem-
The transmission has never had to be rebuilt and I don’t want to start such a big job due to lack of experience on automatics. I would be driving down the road and after the truck had driven a good distance to warm up, it would either seem to loose a little power even at low gears or just pretend it was in neutral all together. I would have to pull over, turn it off and let it cool down, and then drive another 15 miles before it happened again. While it worked, it shifted fine and had all the power like normal. Never felt rough or reved too high to shift.
What my research told me-
Supposedly there are 2 primary culprits that seem to be common for E4OD’s of this era.
(A) the neutral safety switch (or MLPS)
(B) throttle positioning sensor (I think least likely)
I plan to go back towards the end of October and would like to put it in good enough condition that I can bring it back home with me (14 days to work on it). I plan to replace all filters, fluids, gas, tires, and battery before starting it. I will be attempting to use a multimeter to test these possibilities, as well as dropping the transmission pan to look for shavings on the magnet.
So what-
I need some help of a few people that have gotten down and dirty with these series of trucks to tell me if I’m looking in the right direction, as well as other possible culprits. I read close to a hundred forums on this topic, but no one seemed to have the exact same story as me or the story was to vague for me to be sure. Any advice you have to offer would be very appreciated! I just want my truck home.
Life story-
The truck has about 112,000 miles on it and was primarily used as a farm truck until I got it at 16. About 4 years ago, it began having what seemed like transmission problems. Unfortunately, I was unable to do anything due to joining the Army and having to let it sit for 3 years while I was in Hawaii. I’m stationed back closer to it now (300 miles), and would like to get it going again as I had very fond memories of this truck and it’s been in the family since leaving the dealership.
The Problem-
The transmission has never had to be rebuilt and I don’t want to start such a big job due to lack of experience on automatics. I would be driving down the road and after the truck had driven a good distance to warm up, it would either seem to loose a little power even at low gears or just pretend it was in neutral all together. I would have to pull over, turn it off and let it cool down, and then drive another 15 miles before it happened again. While it worked, it shifted fine and had all the power like normal. Never felt rough or reved too high to shift.
What my research told me-
Supposedly there are 2 primary culprits that seem to be common for E4OD’s of this era.
(A) the neutral safety switch (or MLPS)
(B) throttle positioning sensor (I think least likely)
I plan to go back towards the end of October and would like to put it in good enough condition that I can bring it back home with me (14 days to work on it). I plan to replace all filters, fluids, gas, tires, and battery before starting it. I will be attempting to use a multimeter to test these possibilities, as well as dropping the transmission pan to look for shavings on the magnet.
So what-
I need some help of a few people that have gotten down and dirty with these series of trucks to tell me if I’m looking in the right direction, as well as other possible culprits. I read close to a hundred forums on this topic, but no one seemed to have the exact same story as me or the story was to vague for me to be sure. Any advice you have to offer would be very appreciated! I just want my truck home.
Trans codes are available for your truck, you just need to use the old way to get them or find someone that can get them.
You would need an analog multimeter to use , not a digital one.
That is as good a place to start checking as any.
There is a little tool , #443, made by Thexton that comes with directions and can do a lot for you. It will allow you to get Hard Codes, Continuous Codes . AND do Dynamic testing. All this is in the vehicle's computer. The last time I checked the price was around $20.00. Any Ford with OBD I can be accessed with this tool, good investment.
You would need an analog multimeter to use , not a digital one.
That is as good a place to start checking as any.
There is a little tool , #443, made by Thexton that comes with directions and can do a lot for you. It will allow you to get Hard Codes, Continuous Codes . AND do Dynamic testing. All this is in the vehicle's computer. The last time I checked the price was around $20.00. Any Ford with OBD I can be accessed with this tool, good investment.
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