Motor Swap 3100 from 96 monte into 95 Gramnd Am GT

[SlammedAMGT]

from what i can see the motors are exactly the same except for a few extra and missing brackets which weren't a problem, i've got all the mechanics hooked up, trans, motormounts, exhaust, cooling, ext..... the problem i have is all the wiring for the fuel system and sensors is all diffrent i dont know what goes where, a few things matched up but i just can figure anything else out. what i really need to know is where can i find the two wiring diagrams for these cars so that i can match everything up. PLEASE HELP ME!!!!!!!!!!!!!

[Dallas_95GT]

I put a '99 3100 into my '95 GT a few years ago. I remember running into a similar problem. I think a lot of is it due to the fact that the '95 is pre-OBDII where the 96 is OBDII. I *think* I ended up pulling the UIM off, and swapping the fuel rail and injectors. That way all of the electrical connections are the same. Might check out a Hanes or Chiltons manual, they should have all the diagrams you'll ever need.

[SlammedAMGT]

thanks, thats probably what i'll do, i got a hanes but it didn't help much, i'll try chilton

[MantaGreen97]

Yep the injectors from an LG8 (newer 3100) or an LA1 (3400) will throw off any ECM/PCM designed to work with an L82 3100; unless you reprogram for the different injectors, you have to use the L82 injectors.

However both the 96 Monte and the 95 GA would have had L82 3100s. The injectors would be the same; though the harnesses might be different. The EGR will also be different--you might need the special EGR plate to use the 95 (digital) EGR on the 96+ (linear) EGR engines.

The 95 GA might have also had 2 coolant temp sensors (one for the ECM and one for the IPC) whereas the 96+ cars will have only one since the PCM get the data from the one sensor and relays it to the IPC via OBD-II serial data.

The guys over at www.60degreev6.com should be of more help to you. Try posting over there on the forums...

[Dallas_95GT]

I forgot to mentioned the temp sensor.... I've tried a few different things, you can use the sensor that came with the OBDII motor, and figure out which wire does what. However, the gauge will be somewhat off, and I'm not sure how well the pre-OBDII reads that sensor...
Right now I am using the sensor off of my '95 motor on the new motor attached to the block going to the ECM. I then made a coupler on one of the radiator hoses to tap in the sensor for the gauge. That works ok, except the probe on the sensor needs to be a little bit longer. Hoping to find something that works perfectly.

[SlammedAMGT]

I solved the EGR problem cause i saved the upper intake manifiod from the old motor but i didnt think to save the fuel rails and injectors, i was going to buy after market rails an regulator anyway so should i just buy them for the 95 GA 3100 motor so they will match up with the wireing. thank for the link i'll try posting over there as well.