94 7.3l IDI E4OD issues

[Matt Harris]

Hello all my 7.3l 2wd F250 E4OD is having some issues. I know big surprise lol. Trans seems like maybe it is in limp mode. When put in drive it is stuck in what feels like 3rd or 4th, takes off in that gear and does not shift out of it. If I move the shifter to 2nd or 1st it will shift into what feels like 2nd gear. So basically I can shift manually between what I think is 2nd and 4th gear. Reverse and neutral functions normally. My O/D off button does not work and the O/D light on the dash does not work/does not do anything/doesn’t flash. My tachometer is stuck at 250 rpm. I learned through searches that tach signal is needed for E4OD to operate correctly. So I looked into it and tach sensor is good. (2500 ohms resistance through terminals, also puts out constant .5 AC volts at idle, which steadily increases with engine rpm) After verifying sensor is good I pulled the gauge cluster and measured voltage between the tachometer’s ground and signal terminals, it is a constant 2.6v DC regardless of engine rpm, it does not change regardless of engine RPM. So something is not right here. From there I disconnected the TECA (tcm) connector and checked to see if tach signal was there. Had same AC voltage reading as tach sensor did, so signal from tach sensor is getting to the TECA. Also checked all grounds in the TECA connector (good) and checked it was getting power through the power wires (good). So the TECA is getting all power/ground/signal it needs to make the tach work. ALSO when I hook up my obd1 ford scanner to my obd connectors under the hood, the scanner will act like it is not even connected to anything, as if I hadn’t even plugged it in. This is Very odd and makes me suspect TECA is failed internally.

so to recap TECA is getting good ground, power, and tach signal but tach still sits at 250 rpm. (again voltage to tach terminals on back of cluster is not changing)

Yes all my fuses and relays are good. I am suspecting a bad TECA (tcm). What are all your thoughts? What should I check to be double sure that the TECA is toast? Should I go to the connectors on the trans and check for any voltages/signals to see if they are correct? NOTE: this truck just sat for 12 years and I was told everything worked fine when it was parked. Thank you from Washington’s state.

 

[LowTech]

That is exactly what my rig did. I eventually found that the relay in the underhood fuse box was good, but not getting good contact in the box. (mine's an E350, so not sure where your underhood fuse box is) When that happens, and it still does for me, I open the hood and push down on the relay while it's running, I then check by turning off the OD and looking for the light.
I even check after starting, if the light comes on then I dont need to do it and it shifts fine after that.

 

[Exhumis]

Hello all my 7.3l 2wd F250 E4OD is having some issues. I know big surprise lol. Trans seems like maybe it is in limp mode. When put in drive it is stuck in what feels like 3rd or 4th, takes off in that gear and does not shift out of it. If I move the shifter to 2nd or 1st it will shift into what feels like 2nd gear. So basically I can shift manually between what I think is 2nd and 4th gear. Reverse and neutral functions normally. My O/D off button does not work and the O/D light on the dash does not work/does not do anything/doesn’t flash. My tachometer is stuck at 250 rpm. I learned through searches that tach signal is needed for E4OD to operate correctly. So I looked into it and tach sensor is good. (2500 ohms resistance through terminals, also puts out constant .5 AC volts at idle, which steadily increases with engine rpm) After verifying sensor is good I pulled the gauge cluster and measured voltage between the tachometer’s ground and signal terminals, it is a constant 2.6v DC regardless of engine rpm, it does not change regardless of engine RPM. So something is not right here. From there I disconnected the TECA (tcm) connector and checked to see if tach signal was there. Had same AC voltage reading as tach sensor did, so signal from tach sensor is getting to the TECA. Also checked all grounds in the TECA connector (good) and checked it was getting power through the power wires (good). So the TECA is getting all power/ground/signal it needs to make the tach work. ALSO when I hook up my obd1 ford scanner to my obd connectors under the hood, the scanner will act like it is not even connected to anything, as if I hadn’t even plugged it in. This is Very odd and makes me suspect TECA is failed internally.

so to recap TECA is getting good ground, power, and tach signal but tach still sits at 250 rpm. (again voltage to tach terminals on back of cluster is not changing)

Yes all my fuses and relays are good. I am suspecting a bad TECA (tcm). What are all your thoughts? What should I check to be double sure that the TECA is toast? Should I go to the connectors on the trans and check for any voltages/signals to see if they are correct? NOTE: this truck just sat for 12 years and I was told everything worked fine when it was parked. Thank you from Washington’s state.

Can't help you with your problem (sorry) but that's some thorough diagnostics you did. Saving this article.

 

[Cactus Bob]

I am going to get on my soap box and preach, then i will shut up and sit down..........Anyone and everyone who owns one of these trucks with an E4od transmission should have at least one tested transmission control unit in reserve for testing and troubleshooting.....If you do not, get your butt in gear there not making any more and used ones are crushed every day , so get your numbers off your old unit and get on e bay and get you one. when you get it put it in your truck for a month or so and make sure it's good. remove and store. this will save you so much headache in the future.

 

[Robert wood]

Not wanting to get your hopes up or anything, but I was looking to replace my Tcm with an aftermarket one that allowed for changing shift points, firmness etc. I've actually found quite a few controllers for the E4OD but I can't confirm if they are specific for a diesel application or if they are interchangeable between the gas trucks. Mine shifts too damn high in my opinion- idk if thats normal or not.

Sent from my LG-LS993 using Tapatalk

 

[trackspeeder]

Aftermarket controllers will work with gas or diesel.