98pcm temporarily controlling 4L80e questions
09-19-2007, 10:08 AM
#1
98pcm temporarily controlling 4L80e questions Hey all
I have a Z28 with the 402 in my signature and a 4L80e transmission. The car is a 1998 car so it has a 98 pcm. Well, the engine shop ran into an issue with the pcm. They told me the trans guy messed up some wires and now it would not start, but my tuner and I think they (engine shop) had the ignition on when they unhooked the battery and that messed up the theft system on my PCM.
It had a temporary mail order tune on it from PCMforless and as far as I know they do NOT lock their PCMs. Well, regardless, I had to get a new PCM because they 98 one I had was locked. So, I went ahead and got a 99pcm because I was told the 98 pcms will not control the shift sequences on the 4L80e.
The 99pcm is going to be a pain to install. My electrician told me he would look into using a 99 wiring harness to perform the swap, the only other option is to switch out all the pins in the PCMs to match up (out of 80+ pins only 2 are in the same location on the 98-99 PCMs). Either option is going to be extremely time consuming and not cheap. This is my only car right now and I am in a bind.
So, here is my question:
Is it possible to buy another 98 PCM and have the tuner tune it so everything works fine EXCEPT the shift sequences? The transmission guy rigged up some switches so I can manually shift the 4L80e since the 98pcm I had would not shift it. This would be a temporary fix until I have the money and time to have the 99pcm installed. Will everything work fine discounting the fact that I will have to manually shift it? I need input, I MUST get my car up and running. Thanks everyone
Mitchell
I have a Z28 with the 402 in my signature and a 4L80e transmission. The car is a 1998 car so it has a 98 pcm. Well, the engine shop ran into an issue with the pcm. They told me the trans guy messed up some wires and now it would not start, but my tuner and I think they (engine shop) had the ignition on when they unhooked the battery and that messed up the theft system on my PCM.
It had a temporary mail order tune on it from PCMforless and as far as I know they do NOT lock their PCMs. Well, regardless, I had to get a new PCM because they 98 one I had was locked. So, I went ahead and got a 99pcm because I was told the 98 pcms will not control the shift sequences on the 4L80e.
The 99pcm is going to be a pain to install. My electrician told me he would look into using a 99 wiring harness to perform the swap, the only other option is to switch out all the pins in the PCMs to match up (out of 80+ pins only 2 are in the same location on the 98-99 PCMs). Either option is going to be extremely time consuming and not cheap. This is my only car right now and I am in a bind.
So, here is my question:
Is it possible to buy another 98 PCM and have the tuner tune it so everything works fine EXCEPT the shift sequences? The transmission guy rigged up some switches so I can manually shift the 4L80e since the 98pcm I had would not shift it. This would be a temporary fix until I have the money and time to have the 99pcm installed. Will everything work fine discounting the fact that I will have to manually shift it? I need input, I MUST get my car up and running. Thanks everyone
Mitchell
09-22-2007, 10:24 AM
#3
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I'm going to repin my wiring harness to use a 99+ PCM in the next few weeks. Take it slow and label EVERYTHING. It's not that hard, use the pinouts and the threads that are already in the PCM and Tuning forum. Search in that forum for "98 PCM" or something like that. I don't think we have to lengthen any wires, just play musical wires.
09-22-2007, 11:49 AM
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when I got my 4L80E I had to switch to a 6.0L truck operating program for my PCM to work. My tuner just swapped the software and then put my tune in after. Hope that helps.
