LS1/4L60e conversion - trans issues

[clemson_tiger29678]

Just completed a LS1/4L60e into a '72 Vette and the trans is not responding to the computer tune. Engine runs great but the trans is not shifting. The car has been to the trans shop and they hooked the trans up to their scanner and shifted the car through all the gears, so the trans has been eliminated as the issue. When looking at the transmission though the scanner they get nothing. No VSS signal, a default 32 degrees for trans temp and nothing more. I do have 12v to the trans so the power is getting to the trans, but the computer is doing nothing with it. There are no codes on either engine or trans. Basically the transmission can be shifted manually into 2nd and Drive, but no 1st and no OD. Wiring seems to be fine...which only leaves the tune in the computer to be the issue. Any help guys? I didn't do the tune, but rather a friend of mine, and he says it was done by the book. I do know a few things...the PNP wire is grounded-out, per what he read to do. The TCC switch is hooked-up correctly. The shift selector display, where the original 2000 Camaro would show what gear the car was in on the display, has been turned off.

Engine and trans are out of a 2000 F-body. Thoughts? I'll take any guesses at this point. Thanks!

[flame]

Does the pcm have an auto tune in it? Sounds like it is an M6 tune to me.

[clemson_tiger29678]

Does the pcm have an auto tune in it? Sounds like it is an M6 tune to me.

Honestly, I'm not sure, but I'll ask the guy that did my tune. I'm pretty sure he put an auto tune in it and just have in mind that it must be something regarding what has been turned off or left on that shouldn't be...something along those lines. It just seems weird that when you hook it up to a scanner than the computer acts as if the trans isn't even there...doesn't see it.

[Shrek]

Post your tune ... that will answer the auto vs manual tune question definitively.

[clemson_tiger29678]

Post your tune ... that will answer the auto vs manual tune question definitively.

Well, I don't have access to it, the tuner does. The car is going back to him this week for a re-tune...I was just hoping to get some ideas about what was going on before then.

[clemson_tiger29678]

How does the PCM know which gear has been selected? The guy that did my tune took out the part where the gear selection is displayed on the dash of the 2000 Camaro...so when you hook it up to a scanner, it doesn't show what gear the car is in. Could this be the issue? Could it be that the PCM is not seeing what gear is selected...or does the PCM see this from elsewhere? from my understanding, the gear-selection switch/sensor on the 2000 Camaro was on the shifter.

[flame]

The position switches are located insisde the trans on the f-body. Was the pcm originally from an auto?

[wyochimneysweep]

You need to input the selector switch on the side of the tranny to the correct pins on the ECM so it knows which gear it's in

[clemson_tiger29678]

Was the pcm originally from an auto?

I'm not sure. :-/ Buy why would it matter if he did a complete reflash?

[clemson_tiger29678]

You need to input the selector switch on the side of the tranny to the correct pins on the ECM so it knows which gear it's in

Can you speak more to this? I was under the impression as well that the position switches are on the inside of the trans. I'm not sure exactly what you are saying here...shouldn't the above mentioned inside-loacated position switch take care of this? In the tune, should the box that was marked "opitional" for the selector display be left on?

[flame]

I'm not sure. :-/ Buy why would it matter if he did a complete reflash?

I'm only guessing but it sounds to me like the pcm was a manual trans and it has not been reflashed to an auto properly. To make the change you need a auto file and do a write entire. There are lots of tables that we can't see. Just changing things in the manual file and reflashing thinking it will run an auto does not work. The other post about the external switch it is only used on the trucks.

[clemson_tiger29678]

I'm only guessing but it sounds to me like the pcm was a manual trans and it has not been reflashed to an auto properly. To make the change you need a auto file and do a write entire. There are lots of tables that we can't see. Just changing things in the manual file and reflashing thinking it will run an auto does not work. The other post about the external switch it is only used on the trucks.

Thanks so much FLAME! This is more my hunch as well. I'll pass this along to the tuner and see what his thoughts are. Thanks again!

[clemson_tiger29678]

Well guys, it was the tune! Took it back to my tuner and he took about 5 min in putting in a new tune through the OBD II port and BAM, shifts perfect now! Not sure what the issue was with the first tune, could have indeed been for a manual trans, but I'm good to go now! Just thought I would update for future reference.