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98 to 99-02 PCM repin with lots of pictures and videos
So I finally did it. after having my car since 2005, I finally gave up and did the deed lol Ironically it wasn't boost that led me to repin, it was wanting a transmission that would stop turning into a slushy machine!
So i have the 98 trans am, and it was tuned for 2bar Sd Operating system with a built 4l60e until it wasn't. Decided to go 4l80e and of course your can't just throw it in there like the rest of the fbodies, you also have to repin the pcm.
So I got my self a 411 pcm and some new plugs and went to town today.
Was actually alot easier than I thought it was gonna be. need to double check my work and check on couple random wires that the instructions left me with some questions, but over all in about 3 or 4 hours I refined the harness to run a 99+ pcm. Here's how it went.
So these instruction are from MRK, and they sell theor own pcm conversions. I got mine off ebay, but its the same thing. This instructions are LIFE SAVERS!! download them and read them threw a couple time before you begin.
New plug... get them. they will make your life much easier. i got these with the plugs. dont think i needed them, but they are there if you do. here we have my preloaded 411 PCM for my vehile. They even downloaded the 4l80e segment in there for me, as well as a simular build to my car so that the tuning will be easier to start with. heres the old pcm... i know its dirty, but we dont care lol pretty much was my limitation of boost and now the transmission. pulled out the old pcm situating the harness for the disassembly. take off the wire loom and tape. youre gonna need the extra length, and even then, it stills short. didnt realize there was so much space back there. had to pull out some leaves and stuff in the corner heres one of the connecters. these covers come off prety easy but becareful if you wanna save them. they are 20+ years old' so brittle is an understatment. here you are, set those aside heres the back side. not much to do here yet. try to spread the wires apart a tad, but again dont bend or mashem up too much. 10 years ago when people were swapping pcms the wires were fresher. now after 20 years, they might be a bit more brittle. so i got this pcm bracket only ro find out its the wrong one. it pretty, but doesnt fit my apploication. if youre bolting it to a flat surface or inside the xsr then maybe, but i apparently need a 99+ pcm bucket. cant atress this enough.. labke your plugs. old and new and which color especially. once you take the color portions off, theres is almost no way to tell which is which, and as you start moving from one to another, it can be easy to mix up pins and slots if youre not methodical. heres when you actually start repinning. slowly move from your old one, i suggest you start with the first old 98 color, and then work youre way down the sheet until you move on to the next plug. rememebr... slow is smooth, smooth is fast. heres rhe example, ill have a video explaining this more in detail. heres what it starts to look like as you move thruigh the pins. as you can see i have the new ones set up on the cowl, for the first 3/4 of repin, they sit there nicely. but as you get near the end, some of the last rows of wires show that they need to be extended. this is included on the instructions.
Last edited by JoshuaGrooms83; 08-07-2023 at 08:54 PM.
To the OP, if you need ANY help at all in tuning the 4L80E transmission, I offer my help for free. I can help you with adjusting the line pressures, shift points, shift timing, TCC lock up events, etc:... if you need ANY information to properly tune the 4L80E I will help you through it all! I'm so happy that you have made this swap.. If I can be of service, contact me either here on this post, or through messages. All I need to map out a good trans tune for you is tire height measured in inches, rear gear ratio, torque converter stall speed, cam specs (duration at .050" lift) and max RPM you'd like to turn.. You will NEVER regret swapping to a 4L80E.. Trust me... My customers are all smiles once they dump the turd blender otherwise known as the 4LSLUSHY..
lol I appreciate the back story, and yeah each transmission has its place. I had moderate success out of my built 4l60, but the advertised rating was definetly not lived up to. But now that I will be aiming for 1000hp when I build a LQ4 later, I need something that will handle that, and a 4l80e will be better at it.
I appreciate the assistance in lending a hand in tuning the trans segment. I'll need it later lol i have bluecat to help set some of the shift points and adjust gearing, but it still takes time.
As for the wiring, this is gonna take some time lol my fingers hurt from digging out the pins and pulling back plastic tabs, even with picks.
so got it partially complete. need to get the 99+ PCM bucket, as well as some trans related hard parts before I can fore it up. but it's there had some questions on the wiring though.
one wire wasn't listed on the instructions.... so this wire wasnt listed on the repin for the old wiring. what does this go to and do we need it? 98 fbody old Blue pin 24, black with white stripe? its not pretty but its in there. i gotta verify its pinned correctly before i clean it up. surprisingly, no wire extending yet, but its probably gonna need to be later. i have the "delete" wires and the one suspect wire taped until i know i can removed them completely.
Last edited by JoshuaGrooms83; 08-28-2022 at 07:31 PM.
According to Alldata pin 24, blk/wt, circuit 1704, sensor ground jumper,, which according to what I see should go directly to pin 24 on the OTHER connector. So pin 24 on c1 goes to pin 24 on c2...as a Jumper ground between pcm connector c1 and c2.
I used the MRK instructions on my 1998 Z28 M6 and all worked out great (including the tach and fuel gauge) with a 411 PCM preloaded with a tune from Frost, except the 'ASR off' light was always on. I never figured that part out...
Take your time, extend the wires that need it, and organize as you go or it'll end up looking like a rat's nest.
Thanks for the into Jerm. This is also an ASR car 98 Camaro SS. Currently it has the three lights of death lol. ASR INOP ABS INOP RED BRAKE all lit up. Not high on the priority at this time to fix.
When you say the light was always on did the system still work or respond to the button? Or did it deactivate the system entirely?
Thanks for the into Jerm. This is also an ASR car 98 Camaro SS. Currently it has the three lights of death lol. ASR INOP ABS INOP RED BRAKE all lit up. Not high on the priority at this time to fix.
When you say the light was always on did the system still work or respond to the button? Or did it deactivate the system entirely?
The system seemed to not work and the button was unresponsive. The light on the button was off and wouldn't come on. Basically, it's like everything associated with ASR was disabled and the dash light stayed on all the time.
I forgot to post in this thread, as it ties into my 4l80e install. but yes, after I finally combed over every wire, I did find that I misplaced one of my wires that prevented it from starting the first time. forgot which one it was, but I was experiencing either no crank, no fuel pump priming or only fuel pump priming but still no crank. after I went though all the pins, found one out of place. mixed up the red and blue c1 and c2. I also wired in the 4l80e.
currently I have not extended any wires, so its a bit tight but it fits exactly where it's at. I still need to get the bucket for it so it's not just sitting there getting banged around. Already started tuning it. realized I need to swap the MAP sensor from the 2bar to the 3bar. tired of it being on the back of the intake so im gonna remote mount it.
as of today I am fully live tuning the car. had to do an emergency surgery on the MAP sensor harness... turns out when I was repositioning the engine harness and filler tube for the 4l80 into place... I yanked out the MAP sensor wire from the plug end... 🙄 that explains why my sensor wasn't reading when I started to try and tune the csr the second time around. went ahead and did a relocated and Wire Harness extention for the MAP sensor for easier asses, and bam!! Real time tuning is amazing!!! dialed in the idle while it was running in seconds!!! car was pouring fuel into the cylinders lol had 10.5 AFR but it had the chop lol leaned it out to about 14.0 while idling and got rid of the smoke and fuel smell. I can confirm that the pcmwon't read below 40ish kpa with the 3bar map but its nice to be able to smooth out the VE in real time.
07-28-2022, 09:40 PM
98 to 99-02 PCM repin with lots of pictures and videos 
