PCM swap issues
Thread Starter
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
PCM swap issues update
Here is my latest (OF MANY) tunes on my swapped out PCM. I'm having issue with
1. car flaring on start, then settling back around 500 rpm (on 725 command) and shutting of
2. When I place the trans in D or 3, it slips like it is actually in 3rd, but the scanner says it is in 1
See summary below
1. car flaring on start, then settling back around 500 rpm (on 725 command) and shutting of
2. When I place the trans in D or 3, it slips like it is actually in 3rd, but the scanner says it is in 1
See summary below
Last edited by Blow Torch; Apr 21, 2015 at 02:51 PM.
Thread Starter
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
PCM issue update
UPDATE of issues
I have posted parts of this issue, but here is the completed version. I REALLY need some answers to be able to continue.
I swapped out a 98 PCM for a 01 on my 98 Corvette. I repined per a sheet specific to a corvette, then verified by another one. When I started having issues, I pulled it back apart and verified all of the wires were in the correct location per the pin-out sheet. I downloaded the tune, then purchased credits and "bought" the tune. I selected a 2bar and did a write entire to the car. The OS table still has "applied for" on it. I swapped most of my settings over, and the car would not crank. I did the "attempt crank, ign. on 11 mins, off 30secs" relearn, and the car will crank, although it does not idle well.
The real problem is the trans appears to be in Limp mode. If I put it into D or 3, it barley moves. It works fine in reverse.
When I down load a tune, I get codes 1016,1064, 1096 (I believe), but if I clear them and fire up the car, I only get 102, 103. I have a SD tune.
Do I need to change my VIN (I didn't think the 98 and 01 were compatible) or just what.
Any ideas?
I have posted parts of this issue, but here is the completed version. I REALLY need some answers to be able to continue.
I swapped out a 98 PCM for a 01 on my 98 Corvette. I repined per a sheet specific to a corvette, then verified by another one. When I started having issues, I pulled it back apart and verified all of the wires were in the correct location per the pin-out sheet. I downloaded the tune, then purchased credits and "bought" the tune. I selected a 2bar and did a write entire to the car. The OS table still has "applied for" on it. I swapped most of my settings over, and the car would not crank. I did the "attempt crank, ign. on 11 mins, off 30secs" relearn, and the car will crank, although it does not idle well.
The real problem is the trans appears to be in Limp mode. If I put it into D or 3, it barley moves. It works fine in reverse.
When I down load a tune, I get codes 1016,1064, 1096 (I believe), but if I clear them and fire up the car, I only get 102, 103. I have a SD tune.
Do I need to change my VIN (I didn't think the 98 and 01 were compatible) or just what.
Any ideas?
Last edited by Blow Torch; Apr 21, 2015 at 02:48 PM.
Pro
Joined: Sep 2008
Posts: 626
Likes: 1
From: Oswego NY
UPDATE of issues
I have posted parts of this issue, but here is the completed version. I REALLY need some answers to be able to continue.
I swapped out a 98 PCM for a 01 on my 98 Corvette. I repined per a sheet specific to a corvette, then verified by another one. When I started having issues, I pulled it back apart and verified all of the wires were in the correct location per the pin-out sheet. I downloaded the tune, then purchased credits and "bought" the tune. I selected a 2bar and did a write entire to the car. The OS table still has "applied for" on it. I swapped most of my settings over, and the car would not crank. I did the "attempt crank, ign. on 11 mins, off 30secs" relearn, and the car will crank, although it does not idle well.
The real problem is the trans appears to be in Limp mode. If I put it into D or 3, it barley moves. It works fine in reverse.
When I down load a tune, I get codes 1016,1064, 1096 (I believe), but if I clear them and fire up the car, I only get 102, 103. I have a SD tune.
Do I need to change my VIN (I didn't think the 98 and 01 were compatible) or just what.
Any ideas?
I have posted parts of this issue, but here is the completed version. I REALLY need some answers to be able to continue.
I swapped out a 98 PCM for a 01 on my 98 Corvette. I repined per a sheet specific to a corvette, then verified by another one. When I started having issues, I pulled it back apart and verified all of the wires were in the correct location per the pin-out sheet. I downloaded the tune, then purchased credits and "bought" the tune. I selected a 2bar and did a write entire to the car. The OS table still has "applied for" on it. I swapped most of my settings over, and the car would not crank. I did the "attempt crank, ign. on 11 mins, off 30secs" relearn, and the car will crank, although it does not idle well.
The real problem is the trans appears to be in Limp mode. If I put it into D or 3, it barley moves. It works fine in reverse.
When I down load a tune, I get codes 1016,1064, 1096 (I believe), but if I clear them and fire up the car, I only get 102, 103. I have a SD tune.
Do I need to change my VIN (I didn't think the 98 and 01 were compatible) or just what.
Any ideas?
Thread Starter
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
Its odd how this seems to be a straight forward swap, with so many people having NO issues, and now you're the third to say they DID have some issues. (one guy said he had to put his 97 back in, which is what Im on the border to do)
I've also heard that any VIN issues seem to be easier to address with EFI
I've also heard that any VIN issues seem to be easier to address with EFI
Pro
Joined: Sep 2008
Posts: 626
Likes: 1
From: Oswego NY
Its odd how this seems to be a straight forward swap, with so many people having NO issues, and now you're the third to say they DID have some issues. (one guy said he had to put his 97 back in, which is what Im on the border to do)
I've also heard that any VIN issues seem to be easier to address with EFI
I've also heard that any VIN issues seem to be easier to address with EFI
Thread Starter
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
Mine would not fire up until I did the security relearn
Now that it fires up, it will not idle without giving it throttle
It will barely move forward (apparently in 2nd gear/limp mode)
I have checked and rechecked that the pins are in the correct location, and all looks good, but the car is dead in the water and it looks like I will be spending more $$$ on it to get someone to figure it out
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Racer
Joined: Sep 2013
Posts: 469
Likes: 62
From: coconut creek, fl
I will ask my brother goes by douniasg on the forum to post some info
maybe he can help you out. He did a lot of the work
Sounds like it's either a problem with the tune or incorrect placement of the iac and transmission wires. I purchased the pcm and custom tune from LSXtuning on LS1tech and he disabled the VATS so that's why my car started right up. Using 2002 Operating system and 2002 pin out for reference. Yours is a 1998 as well? I had 3 left over wires not being used
maybe he can help you out. He did a lot of the work
Sounds like it's either a problem with the tune or incorrect placement of the iac and transmission wires. I purchased the pcm and custom tune from LSXtuning on LS1tech and he disabled the VATS so that's why my car started right up. Using 2002 Operating system and 2002 pin out for reference. Yours is a 1998 as well? I had 3 left over wires not being used
Thread Starter
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
Thanks Guys
It is a 98 A4 and I swapped in a 01 apparently (by its settings) from a manual. I have checked and rechecked the wiring pin-out. The IAT works, as well as the fuel gauge. There were a few wires that I didn't connect, per the instructions someone gave me that had done a Vette and run into fuel gauge issues.
Is your car a A4 or manual? I haven't been asking, but I wonder if the guys having issues are the ones with A4s, and the successful swaps are manuals
It is a 98 A4 and I swapped in a 01 apparently (by its settings) from a manual. I have checked and rechecked the wiring pin-out. The IAT works, as well as the fuel gauge. There were a few wires that I didn't connect, per the instructions someone gave me that had done a Vette and run into fuel gauge issues.
Is your car a A4 or manual? I haven't been asking, but I wonder if the guys having issues are the ones with A4s, and the successful swaps are manuals
Pro
Joined: Jul 2007
Posts: 587
Likes: 70
I attached the 2 pin outs I used. I didn't follow the function name cause they were different. I went by the the circuit No. and all the wires matched except c1 red pin 24 and c2 blue pin 24 they are both sensor ground jumper I left them out. Also c1 red pin 69 evap purge vacuum switch signal I left out. For 2002 pin out the only pins that didn't get used was c1 blue pin 35 cpp switch signal, c2 red pin 45 evap canister vent solenoid control, c2 red pin 64 fuel tank pressure sensor signal.I installed the new pcm with the custom tune that I didn't do and the car fired right up and drives like it should. I also attached the tune. Good Luck
This has definitely been a strange situation.
Racer
Joined: Apr 2010
Posts: 266
Likes: 10
From: Noble OK
I did the swap on my 97 using GM diagrams. If I remember correctly there were a couple of wires that were listed on the diagrams incorrectly. I made the appropriate changes and didn't have any problems.