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truck:
1996 F-150 4x4, E4OD, 3.55 rear gear
(A few years old now)
So I had the transmission replaced by a reputable guy, I don’t think it’s exactly a transmission problem. Trans fluid is fine, but the rear end could use replacing sometime (the unit not fluid) soon, as the previous owner let the rear end run dry due which has caused some damage to the gears.
but when I seem to do 5%-10% input throttle from the gas pedal, the truck feels like it gets pulled backwards, about every other second, (almost like the rear end isn’t catching?) but if I give it more throttle it’s fine.
It’ll just do it, if I’m driving at the same throttle input, it’ll just happen between that 5%-10% input area.
It’s a bit violent, and I don’t want to destroy anything accidentally
someone I talked to in person said it may be snake biting, not sure what the term really means.
The gears look fine to me too.
What was the transmission doing that it required replacement of hard parts? Was there slipping or something inside broke? That fact that it does strange things based on throttle position seems like a bad TPS input to the PCM. Does it feel like the transmission is going into neutral and slamming back into gear?
I have never heard of that term.
Originally Posted by 96 4x4
…the previous owner kinda beat the ever living hell out of it….the truck was doing all sorts of crazy things.
the only codes I was getting, was something to do with my TPS, but due to the age of the truck being 28, it probably wouldn’t be a bad idea to get a new PCM
Same here. I have no idea what the guy was putting in the bed but I found every leaf in both spring packs were broken.
What TPS codes were you getting? You could end up with a “remanufactured” PCM that is worse than what you have especially since you have not determined that there is a problem with the computer.
Originally Posted by 96 4x4
no no that’s not what I’m saying. I think you may have posted on my other forum, where I was asking about odd shifting, which happened to turn out to be the TPS, I replaced the TPS and it fixed that issue, and someone had brought up testing the wires to the PCM back to the TPS, and it wasn’t exactly in spec.
Your other forum? What other forum are you posting in? So you already replaced the TPS? Did you use a Motorcraft sensor? Does the new TPS have the correct voltages at closed and WOT and have a nice smooth voltage sweep when going from closed to open and back?
Originally Posted by 96 4x4
Do you happen to have a link on how to do so?
A link on how to check the bearings in the differential or fuel pressure or TPS/ MAP sensors?
96,
I think. mine. is going through the same thing. While driving, things feel fine and then it starts feeling like a momentary slip happens and the rpms bump about 100-200 each bump. Feels like something is breaking loose and then re-engaging. I have been chasing this for a year. Just got it back from the mechanic this week, He checked the pcm and the voltage coming from the ppm was bad. Opened it up and several blown resistors and capacitors. Ordered a rebuilt one from Rock auto and the thing would not even run, returned it for another replacement and this one has the truck running fine. He also replaced the Map sensor and the TPS, and it ran perfect for about 10-15 miles and then the slipping, bumping, whatever you call it showed back up. My mechanic warned me that the rebuilt PCM's have very poor reliability so be prepared to replace it again. He was not surprised that the first one was so far off that it would not even idle.
So now I still have the problem and can't figure it out. Have you made any progress? Oh, brought it home and had leaking rear brake line so that is next before tackling the surging, slipping, whatever again. Below is a video from inside the truck. You can't really hear what is happening but I think you may have the same symptoms you are trying to figure out.
96,
I think. mine. is going through the same thing. While driving, things feel fine and then it starts feeling like a momentary slip happens and the rpms bump about 100-200 each bump. Feels like something is breaking loose and then re-engaging….He also replaced the Map sensor and the TPS… Truck surging or slipping video
Carson
What model 1996 with what engine and transmission? I don’t know if you have driven it far enough to set any codes but it doesn’t cost anything to check. Is it safe to assume there were codes set for those sensors and they tested as being defective?
The video is not available unless you have a google account. At least that’s what it told me.
96,
I think. mine. is going through the same thing. While driving, things feel fine and then it starts feeling like a momentary slip happens and the rpms bump about 100-200 each bump. Feels like something is breaking loose and then re-engaging. I have been chasing this for a year. Just got it back from the mechanic this week, He checked the pcm and the voltage coming from the ppm was bad. Opened it up and several blown resistors and capacitors. Ordered a rebuilt one from Rock auto and the thing would not even run, returned it for another replacement and this one has the truck running fine. He also replaced the Map sensor and the TPS, and it ran perfect for about 10-15 miles and then the slipping, bumping, whatever you call it showed back up. My mechanic warned me that the rebuilt PCM's have very poor reliability so be prepared to replace it again. He was not surprised that the first one was so far off that it would not even idle.
So now I still have the problem and can't figure it out. Have you made any progress? Oh, brought it home and had leaking rear brake line so that is next before tackling the surging, slipping, whatever again. Below is a video from inside the truck. You can't really hear what is happening but I think you may have the same symptoms you are trying to figure out.
why anyone would order a chinesium PCM from crock auto is beyond my thinking, ESPECIALLY a "mechanic" when there are plenty of reputable PCM rebuilding services out there that guarantee their work.
have you tried turning overdrive off and seeing if the issue goes away?
why anyone would order a chinesium PCM from crock auto is beyond my thinking, ESPECIALLY a "mechanic" when there are plenty of reputable PCM rebuilding services out there that guarantee their work.
have you tried turning overdrive off and seeing if the issue goes away?
the Part number for my PCM is the one ending in ASA and nobody around had that PCM or offered it. Mechanic told me I could try to find one somewhere but Napa nor his other suppliers had the correct one in stock, so I ordered it from Rock auto, not him. I could not find the correct part number anywhere around here.
Yes, I have tried with OD turned off and it did not help.
What model 1996 with what engine and transmission? I don’t know if you have driven it far enough to set any codes but it doesn’t cost anything to check. Is it safe to assume there were codes set for those sensors and they tested as being defective?
The video is not available unless you have a google account. At least that’s what it told me.
Yes, there were codes for the MAP and he said the wiring on the TPS was in really bad shape so I had him go ahead and replace it too.
What model 1996 with what engine and transmission? I don’t know if you have driven it far enough to set any codes but it doesn’t cost anything to check. Is it safe to assume there were codes set for those sensors and they tested as being defective?
The video is not available unless you have a google account. At least that’s what it told me.
my trans had been rebuilt because it was slipping on turning on those roundabouts to get on high ways, and up some inclines. We also tried to swap the fluid but it was leaking from a spot in which was not fixable i found out.
i have a 5.0L E40D with 4x4 (not a clue off the top of my head what model transfer case.)
A link on how to check the bearings in the differential or fuel pressure or TPS/ MAP sensors?
the MAP test.
additionally, when testing my TPS connections to the TCM, I got an OL, may have been not having gator clips, but in any rate I did end up having a bad TPS
your thread.
