94NAIDI
Registered User
I know this has been discussed over and over again. I tried my best to not start another thread. I read through so many different threads on this site as well as the other diesel truck sites trying to get advice without creating another thread on the same issue. But all the other threads either had different symptoms or the resolution they came to didn’t work for my truck. So I apologize in advance for yet another repeat of the dreaded flashing OD light.
1994 F350 7.3 IDI 4x4 crew cab E4OD transmission.
Here are my symptoms. Truck runs perfectly fine. Transmission seems to shift fine. I can drive the truck for two or three days with no issues. Then randomly the OD light will start to flash out of no where with nothing unusual happening prior. Then of course it goes into limp mode and shifts like crap. Usually if I continue to drive the truck, the OD light will eventually go out. I drove a 4 hour trip last week and the light came on and went back off 3 different times throughout that trip. Also if I shut off the truck, the light goes off and does not come back on when I drive it again. Then without warning, a couple days later it appears. Sometimes, when the light comes on, if I manually shift into first, then second, then drive taking off from a stop light the light will go out. I do this a lot when the light comes on to avoid it slamming itself into gear in limp mode. I don’t know if that is telling us anything or it’s just purely coincidental. I did notice today that the shift to 3rd and then 4th happen really fast. Almost so fast you don’t notice 3rd at all. I’m staring to question if that is normal or not. My truck will literally be in 3rd for maybe a second or two at most. And usually the shifts take place simultaneously to where you don’t even notice 3rd at all. I have to watch the rpm gauge to even notice the 3rd shift and it immediately goes to 4th. I don’t know if I’m just getting overly sensitive to the tranny at this point or if that is a legit symptom.
Here’s what I have done to solve the issue based on my research of other threads. Replaced VSS. Replaced the 100uf capacitor that is known to go bad on the PSOM. Unplugged, inspected, cleaned, applied dielectric grease, and plugged back in the connectors at the VSS, the transmission selector switch, the solenoid pack, and the TPS. I also adjusted the TPS to 1.2 volts at idle. It was at 1.08. I unplugged and checked every fuse in the cab as well as in the distribution box. Did a tranny fluid and filter change. All the above seemed to help my tranny shift even better. But unfortunately I am still getting a random flashing OD light. I ran the codes just today and came back clean. 011 no codes found. That was KOEO and KOER tests. Both found no code. The only thing is my light is not currently flashing. So I don’t know if the light has to be actually flashing for a code to be pulled. I will keep the code reader with me to run them next time it happens. Because the flashing goes away a lot of times before I even get home.
I have done everything I can think of, and everything I found in my research. Does anyone have any other tests I can do or advice. This is an extremely challenging issue for me to fix. I don’t mind spending the money to fix it. But I don’t want to waste money either. I need to find the smoking gun so I can get it fixed once and for all. I appreciate any help and feel free to ask questions. There may be more symptoms I’ve forgotten
1994 F350 7.3 IDI 4x4 crew cab E4OD transmission.
Here are my symptoms. Truck runs perfectly fine. Transmission seems to shift fine. I can drive the truck for two or three days with no issues. Then randomly the OD light will start to flash out of no where with nothing unusual happening prior. Then of course it goes into limp mode and shifts like crap. Usually if I continue to drive the truck, the OD light will eventually go out. I drove a 4 hour trip last week and the light came on and went back off 3 different times throughout that trip. Also if I shut off the truck, the light goes off and does not come back on when I drive it again. Then without warning, a couple days later it appears. Sometimes, when the light comes on, if I manually shift into first, then second, then drive taking off from a stop light the light will go out. I do this a lot when the light comes on to avoid it slamming itself into gear in limp mode. I don’t know if that is telling us anything or it’s just purely coincidental. I did notice today that the shift to 3rd and then 4th happen really fast. Almost so fast you don’t notice 3rd at all. I’m staring to question if that is normal or not. My truck will literally be in 3rd for maybe a second or two at most. And usually the shifts take place simultaneously to where you don’t even notice 3rd at all. I have to watch the rpm gauge to even notice the 3rd shift and it immediately goes to 4th. I don’t know if I’m just getting overly sensitive to the tranny at this point or if that is a legit symptom.
Here’s what I have done to solve the issue based on my research of other threads. Replaced VSS. Replaced the 100uf capacitor that is known to go bad on the PSOM. Unplugged, inspected, cleaned, applied dielectric grease, and plugged back in the connectors at the VSS, the transmission selector switch, the solenoid pack, and the TPS. I also adjusted the TPS to 1.2 volts at idle. It was at 1.08. I unplugged and checked every fuse in the cab as well as in the distribution box. Did a tranny fluid and filter change. All the above seemed to help my tranny shift even better. But unfortunately I am still getting a random flashing OD light. I ran the codes just today and came back clean. 011 no codes found. That was KOEO and KOER tests. Both found no code. The only thing is my light is not currently flashing. So I don’t know if the light has to be actually flashing for a code to be pulled. I will keep the code reader with me to run them next time it happens. Because the flashing goes away a lot of times before I even get home.
I have done everything I can think of, and everything I found in my research. Does anyone have any other tests I can do or advice. This is an extremely challenging issue for me to fix. I don’t mind spending the money to fix it. But I don’t want to waste money either. I need to find the smoking gun so I can get it fixed once and for all. I appreciate any help and feel free to ask questions. There may be more symptoms I’ve forgotten