Just the other day noticed that my kick down / passing gear was not working. I have found many posts but just not one that addresses my specific problem. For background, per my build codes, have an M30 automatic 4 speed electronic transmission (AUTOMATIC 4 SPEED, 4L60E,ELECTRONIC). Is it possible that the problem is associated with one of the shift solenoids or could the problem be associated with other components / adjustments? Thanks Bob
No kick-down/passing gear at any speed? Or only at hiway speeds? Sounds like a "failsafe" mode, indicating the system has a code set. You need to scan, or have the vehicle scanned to see what code(s) it has, and go from there. Being a '94, it will not be an OBDII system, so you will need the earlier OBD capable scanner to pull codes.
Another way to pull codes is by jumpering two terminals in your ADLC(Assembly line Data Link Connector). Jump terminals A&B(key off), then turn key on, and watch the Check engine/service engine) light. It will flash the codes. As an example, code 12 will appear as 1 long flash, and 2 short flashes. Each code will flash 3 times, then the next code(if any more are present) will flash. Once all codes have been shown, it will cycle thru them again. Once you find out what codes you have, we can do a proper diagnosis.
Joel Adams
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Thanks. Will do. Bob
Pulled my codes and got an 81 'Transmission Shift Solenoid B open or shorted". Talked to local transmission shop and was told that mostly is the problem - he is checking it out. Thanks for the response. Bob
Would definitely explain the problem you are having. I would suggest checking the external harness/wiring where it goes into the trans first, to make sure there are no bare/nicked wires around the connector. The wiring GM used then(and now too) is prone to the insulation failing. This can cause wires to short in that area. If all looks well there, then I would go after the solenoids. In my experience, it's best to replace BOTH of the shift solenoids at the same time, since you are there. Both the "A"(1-2 shift) and "B"(2-3) solenoids are the same solenoids. The harness connectors are likely to be brittle, and may break as you disconnect them. They will still work fine, as long as they are plugged back into the new solenoids all the way. Be aware that one of the solenoids has a spring loaded valve behind it, and it might pop out unexpectedly, so keep a hold of them as you remove the clips that hold them in, and remove them slowly. Not a hard job at all to do, really. Couple of hours labor, even jacking it up, using jack stands, and pulling the pan.. This is all assuming you are going to do this yourself. If your trans shop is doing it, then they should already know all of this! 😄
Shift solenoids should run around $30 or less(each).
Joel Adams
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Being a '94, it will not be an OBDII system, so you will need the earlier OBD capable scanner to pull codes.
Another way to pull codes is by jumpering two terminals in your ADLC(Assembly line Data Link Connector).
For the record, the '94 -'96 Corvettes all had the 16-pin OBD2 diagnostics connector and can be accessed with a Tech2. Finding a buddy with a Tech2 is the hard part (we have 2, 1 handheld and 1 laptop).
Thanks for the responses. Just FYI. The problem was my B shift solenoid. Had the A and B solenoids replaced and problem solved. Thanks again Bob