Sierraguy

New to the forum. I have a freshly rebuilt 94 4l60e that after reseting the Ecm it goes back into limp mode. I have to reset the Ecm every day to drive it or if I don't use the truck for a few hours I have to reset the Ecm. Once I do this the transmission will shift just fine until it sets for an hour or so.. Any I sight would be greatly appreciated. The transmission besides new parts from the rebuilt it also has a new separator plate and a new internal wiring harness. Thanks for your help and for allowing me to join..

bbond105

You need to scan the vehicle for engine and transmission codes. Some codes will cause limp mode.

Sierraguy

What is a goid scan tool for this old of truck?

dixiebandit69

A paper clip plugged into the A and B terminals of the diagnostic port. Then count how many times the check engine light blinks.

It should always start and end with code 12.

Y2K-WS.6

iTrader: (1)

You need an OBD 1 code reader. I have an Innova 3140 that I've had nearly 20 years. It reads both OBD 1 and OBD II with 2 different cables one with matching plug for each system. Now this one is somewhat dated but there are similar more modern versions available. These scanners are an absolute necessity in my opinion if you own any computer controlled vehicle to give insight into the problems your vehicle is having.

FranksCustomTrans

Also call round known older garages .Many still have their old snap on scanners laying around and can scan it. Also you can check on a cable USB to ALDL cable and several programs online that can read codes and some data that way. But as mentioned if you have an older vehicle you plan on working on and keeping the ability to scan it is imperative.
But without some method to read codes or data even better , You are chasing your tail throwing parts at it .

Sierraguy

I did the paper clip and got code 66. This states that there is an open circut in the 3-2 shift solenoid the only problem with that is I don't have a 3-2 shift solenoid. I have a 1-2 & 3-4 ( A & B ) . I still have the original solenoids that were taken out when the transmission was rebuilt. I checked them for resistance and according to Google they should have between 12- 28 ohms,. Both of my old ones have between 20-21 ohms. And when they are supplied with power they click open and closed. I'm thinking of putting them back in the transmission to see what happens.

bbond105

The 3-2 solenoid is round and located at the front of the valve body near the manual valve linkage. Reinstalling your old A-B solenoids would be a waste of time and fluid.

Sierraguy

Update: I changed the 3-2 shift solenoid and she is shifting great. No issues. Thanks everyone for the help on solving this issue. THANK YOU....