Alright, so here's whats going on. e99 f250 powerstroke. I went to work last night, truck drove fine on the way home no problems at all.Trans temp might have been around 140 i think, no more then 150. Got early early this morning to go to work and started the truck and the o/d light was flashing. Tried putting the gear selector in D, engine stalled. Restarted and tried in R, truck stalled. Basically felt like the TC was locked up and obviously couldn't move the truck at a stop. Figured i didn't have the time to mess with it and jumped in another truck and went to work. When i got home 8 hours later, i started the e99 up again, no O/D light, put it in gear, no stalling, Drove truck, and it drove fine. Tried pulling codes, there were no codes. Any clue what might have went wrong? Maybe a torque converter lockup solenoid, or clutch pack solenoid. VSS? Anyone had this problem before?

 

What did you use to read for codes? If the OD light was flashing, there should be a code.

 

Well i borrowed the scan tool from a friend at work. Its a older snap-on Fast Track mt2500. It should have read trans codes i was sure, but none showed up.

 

Your TC is definately engaged,

Have you fooled around at all with the wires doing a lockup mod?

 

Nope, not at all. Haven't touched really any wiring on the truck yet except gauges and lights.

 

Check the fluid level. Low fluid will do that.

 

Level check is good. Good before running, and good while running.

 

did you ever find out what was wrong? I have the same issue

 

Then you need to check for codes. You probably can't fix it without knowing the codes.

 

yup, the only code it has is p0720 oss has been replaced, here is a link to the thread
https://www.ford-trucks.com/forums/1...ng-issues.html

-thanks

 

Did the new sensor eliminate the code?

I'm not chasing multiple threads on one issue.

 

no it did not eliminate the code, when the truck is first started there is no OD light and no whine from TC after about 3 mins the light will flash and the TC will start to whine. if I delete the code the whine immediately goes away but soon comes back. If you shift to D while the light is flashing it shifts hard (TC locked)

 

Then you need to fix what's wrong with the OSS. Since you replaced the sensor it probably is a damaged wire between the OSS and the PCM. Sometimes it's just easier to run a new wire than to find where the damage is.

The whine is the pump working harder because when a code is stored the trans goes into FMEM (Failure Modes and Effects Management) and the pressure is set high to prevent further damage.

 

Thanks mark, I will run a new wire and see if that takes care of the problem. Just curious if I cut the TC wire at the trans will it take it out of limp mode and drive normally other than the TC not locking?

 

No, probably not.