E4OD Limp mode

[ISPKI]

Hey all. So my new to me 94 super duty was in limp mode when I first got it. I pulled codes, said fluid temp was too high. Drained the fluid, replaced filter and filled with wolf synthetic. Been driving it for a month now, put maybe 150-200miles on her. Tripped flashing OD light today on the way to work.

It has been shifting funny, feels delayed to me, kinda like it wants to shift but waits till it's higher in rpm to do it. I noticed the FIPL is swung all the way to the top of it's bracket. Haven't been able to check voltage on it yet.

IP timing is also off by 4 degrees. I don't think that would cause the limp mode but maybe the combination of that and the FIPL being way out could cause it.


Hopped in and drove home for lunch and the OD light is off again.

 

[aggiediesel01]

Chase down all the sensor inputs to the TCM and check the wiring harness connectors for loose, corroded, burnt contacts. Tach Sensor, Speed sensor in the rear axle, FIPL voltage, MLPS values in different gears, and make sure the Brake light bulbs and contacts are clean and working correctly (check the 3rd brake light too if you're truck had one), also the hazard circuit in the multifunction switch/turn signal switch module which powers up the rear brake lights. Sometimes if the truck has a trailer plug added without actually having the Ford tow package installed there can be issues with the brake light circuits having shorts or high resistance to ground after all these years. The brake light circuit is tied into the TCC solenoid circuit so if it's not balanced correctly it can cause locking/unlocking of the TCC which is normally engaged in 3rd and OD. Also make sure the condition of the wiring harness and connector where it goes into the Solenoid pack is in good condition and not chaffed through anywhere.

 

[ISPKI]

Chase down all the sensor inputs to the TCM and check the wiring harness connectors for loose, corroded, burnt contacts. Tach Sensor, Speed sensor in the rear axle, FIPL voltage, MLPS values in different gears, and make sure the Brake light bulbs and contacts are clean and working correctly (check the 3rd brake light too if you're truck had one), also the hazard circuit in the multifunction switch/turn signal switch module which powers up the rear brake lights. Sometimes if the truck has a trailer plug added without actually having the Ford tow package installed there can be issues with the brake light circuits having shorts or high resistance to ground after all these years. The brake light circuit is tied into the TCC solenoid circuit so if it's not balanced correctly it can cause locking/unlocking of the TCC which is normally engaged in 3rd and OD. Also make sure the condition of the wiring harness and connector where it goes into the Solenoid pack is in good condition and not chaffed through anywhere.

Yeah I will have to track that down. The truck was caked in mud and this drive was right after I power washed the underside and first drive in the rain. Maybe some water seeped into a loose connector.