Hello Everyone New Here And In Need Of Help Swapping a LG8 For A L67

[JimSWylie]

I have recently Swapped out a LG8 in a 2002 GP SE with a l67 out of a 1998 GP GTP . The swap went well except a few minor problems to work out.

For the record i swapped the fuel tank with the 2 speed fuel pump and the remotely located fuel evap system, the 4t65e changed to the hd dif and axles, fuse relay center, pcm, and engine harness with the fuel pump resistor.

Both of these cars were running with O computer issues

I also have both cars complete

Now The problems:

P1651 fan control relay or QDM "B" Fault

P0134 o2 sensor circuit no activity detected bank 1 sensor 1

P0171 system too lean bank 1

P1133 HOS2 B1-S1 insufficient switching

P1651 Fan control relay or QDM fault

P1672 low engine oil level lamp control circuit

P1115 E CT circuit intermittent high voltage

P0730 incorrect gear ratio

ABS not working either

range selection indicator on dash cluster not working

low coolant level indicator light comes on as service engine soon light (so it appears)

low oil level light comes on in park-neutral-3rd-1rst

I believe i need to change some pins under fuse relay center but having 0 luck finding any info on this. Also i have found out that the wheel speed sensors are wired differently in harness

any one to shed some light on this would be awesome

[l67ss]

Bcm wohld proly b tbe cause of the shift range issue

[White93z34]

Wow. Well for starters what harness are you using to run the engine?

 

In your case a most of those issues are probably year-to year wiring changes, Ideally a 2002 GTP engine harness would probably allow most seamless swapping, if you were to change back to a single speed pump, a N/A 02' harness would work just fine with exception to getting the BBV working and relocating the MAP, but those are pretty trivial things.

 

If you continue to use the original transmission you will need to adjust the tune for the different gear ratio since the PCM is expecting 2.89s (or whatever it is the L67 cars come with) rather then your (likely) 3.29s.

 

I'd strongly recommend changing up your harness to a 02' one of some sort as well as the PCM. I'd wager those are the biggest sources of your issues. It would probably help to get the PCM for the proper year (or flash yours to comply) and using the vin of the car to hopefully get the BCM to play nice.

[JimSWylie]

Wow. Well for starters what harness are you using to run the engine?

 

In your case a most of those issues are probably year-to year wiring changes, Ideally a 2002 GTP engine harness would probably allow most seamless swapping, if you were to change back to a single speed pump, a N/A 02' harness would work just fine with exception to getting the BBV working and relocating the MAP, but those are pretty trivial things.

 

If you continue to use the original transmission you will need to adjust the tune for the different gear ratio since the PCM is expecting 2.89s (or whatever it is the L67 cars come with) rather then your (likely) 3.29s.

 

I'd strongly recommend changing up your harness to a 02' one of some sort as well as the PCM. I'd wager those are the biggest sources of your issues. It would probably help to get the PCM for the proper year (or flash yours to comply) and using the vin of the car to hopefully get the BCM to play nice.

 

Im using the pcm, wire-harness,and the two speed fuel pump from the gtp car. today im going to swap the bcm that went with the gtp and what if any changes. If no luck that than i will start searching for 2002 gtp engine harness, pcm, and bcm. As of right now i do not know anywhere to do any flashing. THANKS FOR THE INPUT BTW!

[White93z34]

If you are dead set on using the older harness, at least get a manual for each car and verify the wiring and change where needed to make it work. I'm sure a lot of changes in the harness happened between 98' and 02'

 

I doubt ABS will work since it was a totally different setup in 98 with no traction control.

 

As for the transmission, it will not shift right till the gear ratio is corrected in the tune.

 

And honestly, if you even found the right harness, I'm 90% sure your existing PCM, or even the old L82 one could be flashed to a proper bin file. Actually... and I don't have a gen2 to do it on but If I could find a person willing to let me use their car for it. I could flash a correct bin on your original 3100 PCM and correct the gear ratio for your car along with set the Vin to the one of your cars so the BCM is happy.

Edited January 24, 2014 by White93z34

[JimSWylie]

If you are dead set on using the older harness, at least get a manual for each car and verify the wiring and change where needed to make it work. I'm sure a lot of changes in the harness happened between 98' and 02'

 

I doubt ABS will work since it was a totally different setup in 98 with no traction control.

 

As for the transmission, it will not shift right till the gear ratio is corrected in the tune.

 

 

And honestly, if you even found the right harness, I'm 90% sure your existing PCM, or even the old L82 one could be flashed to a proper bin file. Actually... and I don't have a gen2 to do it on but If I could find a person willing to let me use their car for it. I could flash a correct bin on your original 3100 PCM and correct the gear ratio for your car along with set the Vin to the one of your cars so the BCM is happy.

 

As of right now im looking into getting an 02 gtp harness and looking into programing the pcm. I think i like the higher gear ratio also.

[Imp558]

Alldatadiy.com if you search for "Alldata coupon codes" online you can get complete schematics and a lot more pretty cheap for both cars. You view them online, then trace those problems one at a time by comparing them. I suspect you may have an issue where some of the indicators are serial data communications on the newer car and wired on the older one, but that's just a guess. Either way there's some stuff likely at c100 in the wrong places but the pins aren't brain surgery to extract and move.