E4OD electric gremlins

[dan-o]

I feel your pain. Mine ('89 idi) had/has the same issue with the tach. Tach reading 0, tranny won't work. Tach reading, tranny shifts great. I replaced the ECM with a rebuilt one. Not much better until one day the wife hit the dash console hard ( on purpose while she was cleaning ) and the tach started to work. It's got to be a bad connection or ground wire in there. Somewhere. I haven't had time to pull it all apart and if it quits ( rarely anymore) it will start working again pretty quick.
Thanks, GNATHV, for the diagram!
P.S. I really hate wiring issues...

 

[Noiseydiesel]

I used to have an E4OD. I have found that a lot of problems can be traced back to a faulty range selector switch. You may also want to chase down the 6 grounds and clean those up. Wire brush and a dab of grease.

 

[okie]

I've been looking everywhere for that info. THANK YOU!
Also I haven't been able to locate the TECA relay on the truck; is it in the engine fuse box? Also is the TECA behind driver kick panel and if so what's behind glovebox?

 

[JeffKPDX]

When you replaced your VSS did you check your tone ring? I had a similar issue and my tone ring teeth had been damaged. Replaced that and it was all good.

 

[JeffKPDX]

Yes, TECA relay is in engine fuse box. Bottom right I believe but there should be a sticker on inside off fuse box with layout. And yes the TECA lives behind driver side kick panel.

 

[okie]

What's behind glovebox that looks like TECA with smaller connection?

 

[trackspeeder]

What's behind glovebox that looks like TECA with smaller connection?

RABS module.

 

[okie]

Yeah that's what it looks like. thanks

 

[LocoCanada]

Did you ever solve the problem of no power to the teca, not being able to read codes? My 92 has the same problem