Just started having a transmission problem with my 94 w/ 351, E4OD tranny and 115k miles. It just recently started this behavior toward the end of a 600 mile highway trip where speeds averaged about 82mph but did get higher. (It did not exhibit this behavior the previous three times I ran that 600 miles.) It has done it about a dozen times intermittently. Went about 60 miles the other day and it did it 4-5 times, but not at all on the return trip.
While running between 70-82mph at a consistent speed the RPMs will be about 2200-2500. All of a sudden it will jump to the mid 3000rpm range but immediately back to where it was within a second. Feels like briefly slipping out of gear for a second. It is not happening when climbing a hill or during hard acceleration, just cruising along on the flats at a steady speed. Did it maybe 4-6 times over a couple hours toward the end of the trip. FYI, my cruise-control is not functional. Has only happened once at lower speeds around 30mph.
Fluid level has been checked. Only codes I pulled was a 539 at KOEO and 122 which makes no sense since I replaced the TPS a few months ago, and idle is RPMs seems great while at idle or cruising. Only codes at KOER was 311 which I always get due to the previous owner’s smog pump delete.
I was hoping I would get a code indicating a bad MLPS but that’s not indicated. I haven’t diagnose the problem yet from my searching/reading here. I’ve had several vehicles in the past with problems with the Ford E4OD and they always start slipping in the lower gears and usually start having problems getting into first or first to second when it’s cold out and not yet warmed up. Opposite of the problem I’m now having. Previous owner said transmission was rebuilt several years back but I have no info or documentation on that. Who has seen similar problems? Suggestions on diagnosing the source of the problem?Thanks

 

Ford never put an AOD behind a 5.8L engine in these trucks. Did someone swap the a 5L for the 5.8L engine? 5L trucks could come with an AOD or E4OD. Starting mid-1994 or so the F150s started using a 4R70W instead of the AOD.

False neutraling is a common symptom of a failing MLPS that will never throw a code.

What is a "IPS"?

 

thanks for noting my errors. I’ve edited/corrected. It’s the E4OD tranny and I miskeyed or autocorrected IPS and meant TPS throttle position sensor.

 

Code 539 (KOEO): A/C or Defroster ON during KOEO test

 

hmmm. Had to look at my notes again… had a 122 also. The 539 would be correct since I forgot and had my ac on during the first test.
thanks

 

What phase of the test did you get the 112 code?

 

122 was during the continuous memory code retrieval.

 

Sounds more like the torque converter unlocking.
What size are your tires?
Do you have LED lights in the rear?
How is your third brake like working behind the cab?

 

255-70r15
no LED lights and brake light working fine.

 

Did you clear the code after replacing the TPS?

 

probably not. Will have to lookup how to do that. Didn’t think it was pertinent to this problem so wasn’t too concerned.

 

I agree with rla2005, look at your MLPS.

 

thanks, going to order one today once I get the correct part # figured out.

 

Ford Part# F5TZ-7A247-AA (discontinued)

STANDARD MOTOR PRODUCTS NS94

 

Thank you. yeah, that’s what I had. As usual with discontinued parts I always find multiple replacement numbers that show as the correct replacement…
Trying to get an actual Motorcraft but the vendors that give me an in-stock motorcraft that they says fit, research on that # on other sites says it’s not a fit. Guess I’ll have to go with a Duracraft or similar.