OS Question

[white.lightning]

Hello
I currently have a 1998 Pontiac Trans Am LS1 T56/M6 and your MPVI Pro software.

This winter I am swapping a 4L80e transmission into the car. I purchased 12200411 (2001-2002 F-body) PCM with the 2002 F-body automatic tune (OS) in it. I am changing my engine/trans harness to a 2001-2002 A4 harness and adapting the 4L80e pigtail to it.

What exactly do I need to do in order to begin tuning the car?
Do I need to download a truck tune from say a 2003 Silverado w/ a 4L80e and have HPT modify that?
Do I need to send my 2001-2002 PCM into HPT to have it modified?

-------Taken from a Ls1Tech sticky:

"~ The PCM "WILL" control the 4l80e. Ive seen this alot on here where people say you have to buy a standalone contoler from TCI. If you want to go that route then thats fine but the stock PCM will control the 4l80e. You will have to have the PCM flashed with a new operating system. I simply pulled the .hpt or .bin file from my car, and also found a stock 4l80e truck .bin emailed it to Keith at HPtuners and he fixed it to reflect the new OS to control the 4l80e. You can have EFIlive do this also, but you, yourself can not make these changes.

~ 98 PCM's will not control the 4l80e. There are a couple alternatives for 98's. You could run a manual valve body meaning you shift gears yourself. Or you can control the 4l80e either with a TCI stand alone controller or the BS3. The BS3 has a module where you can contol any GM trans just like you would with HPtuners, EFIlive, or LS1edit. You could also swap out the PCM for a 99+ PCM then have the OS changed. (thanks obZidian!)"

-------Why is this change needed???


Thanks for the help
Andy

[69lt1bird]

Go read this:

http://www.hptuners.com/forum/showthread.php?t=25964

[white.lightning]

Ok. So that answers my question. I saw that thread on tech. I was just confused with the sticky saying "send it to Keith....".

I already have a 2002 A4 tune in the new PCM so I am set. I will just re-pin the 4L80e trans plug accordingly and go from there.

Thanks

[RWTD]

Yeah, don't swap the harness, or you'll be kicking your ass when you find an extra plug you don't know what do to with (Doc on LS1tech has the fix for this). Just repin your factory PCM harness, flash in the proper OS with the trans and fuel segments, and you are good to go.

[RWTD]

Here's you a 2002 F-Body file already made up with the 4L80 segment swap, as well as the 2002 Express Van fuel segment swap, courtesy of EC_Tune:

http://www.hptuners.com/forum/showpo...10&postcount=3

You MUST do a "Write Entire", so don't forget.

...and here are the instructions on how to do the repin of the 1998 harness updated to 1999-2002:

http://www.hptuners.com/forum/showpo...85&postcount=2

[white.lightning]

Thanks for the replies and info!

I have already purchased a new harness. It should be a one for one swap. I am going to investigate it when it arrives next week. The reason I purchased the wiring harness was to avoid a re-pin. I have been reading the ECT and possibly more sensors might be a little different from 98 to 02. For instance I was reading the ECT sensor had 3 wires on a 1998 and 2 wires on a 2002. Are there any other ones that are known?

I was not aware of the fuel tank issue. There is an article on tech:

4L80 tune no longer required

It says that a 4L80 segment swap is no longer needed. I could simply use a 2002 A4 tune. Now I'm trying to find out if the fuel gauge is still an issue. If it is, I might just grab an aftermarket gauge and make it work.

Thoughts???

[RWTD]

There are 3 plugs on the newer harness, one you will not be able to use. Like I said previously, the only individual that knows how to get the newer harness to work on the '98 is "Doc" on LS1tech. Regardless, you are going to have fuel tank issues, gauge cluster issues, and of course the ECT issue.

Why don't you just do what is easiest and do what 99% of everyone does for this (what my previous post said). There is nothing hard about repinning, and everything works as suppose to.

BTW, I don't agree with that a segment swap on the trans is not needed. There's additional/different logic on the trans cal that the 4L80 needs for proper control. As for the unlocking of the TCC when letting off the throttle, this is something easy to rectify in the tune - if the parameter to control it is not there, Chris could easily add it in, so just request it.

[slow67]

BTW, I don't agree with that a segment swap on the trans is not needed. There's additional/different logic on the trans cal that the 4L80 needs for proper control. As for the unlocking of the TCC when letting off the throttle, this is something easy to rectify in the tune - if the parameter to control it is not there, Chris could easily add it in, so just request it.

The logic between a 60e and an 80e is really not that different (otherwise my 80 wouldnt run on a 60 tune). I agree that its silly that I have to run an 60 tune to keep my tcc locked up, however it does open up a new avenue for those whose pcm cant do the 80e (lt1s, 98 f bodies, gtos, etc).