I have noticed that my check engine light has been going on and off everyonce and a while when i drive. I put my code reader on and seems to have found the overdrive control not being seen or unable to shut off? My question is what can I do to fix this? Is this something that needs to be adressed quickly or maybe its nothing?

 

That's a first for me, in the abnormal behaviour list of the E4OD I've never heard of this. If the Transmision seems to be working fine otherwise, I would inspect the wires going to the trans. But I wouldn't worry too much.

 

Yea it seems to be fine but sometimes holds the revs a bit long and the light would pop on I let off it seems to shift then the light goes off. Seems odd but I thought maybe it was an electrical issue since I seem to be having grounding issues with a new fuel pump

 

Are you running the KOEO/CM tests or KOER?

 

Not sure what that really means I'm going to assume that its a koer

 

KOEO is when you do the test for codes with key switched on but with engine off (not running). KOER is when you do the test with key switched on and with engine running.
For what it`s worth I would think your problem is that you did not operate the OD button when prompted during the test. So I would think there is no problem, however rla is the man and hopefully will give an informed opinion if you give him the info he wants.

 

You give me way too much credit Lazy K! But you did hit the nail on the head with the KOEO definition and suspicion of what the OP probably missed during the KOER test.

You need to run the Key On Engine Off (KOEO) tests, the Continuous Memory (CM) codes if any will display after the KOEO tests complete. The CM codes are a view of what happened in the past. You stated the CEL had flashed a few times, CM will probably have stored codes.

 

Were there any other codes present? All codes affect transmission operation on trucks with the E4OD and 4R70w since the one computer controls both devices, and the late shift that responds to throttle change suggests a potential TPS issue that you need to address.

 

Yes the key on engine running is how I tested it. I got two other codes about the rpms going up or down? I dont recall them off the top of my head but I will be testing the codes again tommrow and see what we get.

 

During the KOER tests the PCM is expecting user input such as turning the O/D switch off/on, blipping the throttle, etc. If you do not do them in time or sequence then you get these erroneous "codes". Anytime you are having issues and/or a Check Engine Light (CEL) start with the Key On Engine Off (KOEO) tests and CM readout.

 

Alright so this might sound silly but we couldnt get it to read with just the key on just when the koer

 

OBD I diagnostics have a precisely-defined manner in which the systems are tested and codes are extracted from the computer.

See Fuel Injection Technical Library » How To Run a Self-Test

 

OBD I diagnostics have a precisely-defined manner in which the systems are tested and codes are extracted from the computer.

See Fuel Injection Technical Library » How To Run a Self-Test

 

Which code reader are you using? My Actron and Equus 3145 work flawlessly on several different EEC-IV equipped trucks over the years.

 

This is the one I have.

Amazon.com: Equus 3143 Ford Code Reader 1981-1995 Ford OBD I: Automotive