Thread: New Updates! After swapping 98 gp gtp 3.8 s.c. into a 2002 gp se car

Come on someone, 33 views and no ideas

I also swapped out the dics
Ive heard of something about that but have found it yet

okay banging my head on this for the last three days hears what i come up with -
The engine runs great idles smooth, at wot a little cutting out around the 4,000 rpm range and up, but still pulls hard
when this occurs these dtc's pop up - P0134-O2 sensor circuit no activity detected, P0171-system to lean bank 1, P1133-HOS2 B1-S1 insufficient switching, P1115 E CT circuit intermittent high voltage, P0730- incorrect gear ratio = THESE ONLY POP UP AT W.O.T.=
These DTC's will clear and stay cleared until W.O.T. occurs.
D.T.C. that are on constant and do not clear are - P1651-fan control relay or QDM 'B' Fault and P1672- low engine oil level lamp control circuit.
Still the range selector in the dash cluster not working right and temp gauge in dash also not working. Fan 1 never comes on but fan 2 does come on at 226 degrees.
None of this was going on in the doner car.
Ive went through checking all my relays fuses and sensors.
Would it be the best to get a 2002 engine harness, pcm, and relay control center assembly?
Until i get this figured out im using a code scanner that monitors live data to watch engine temp and temporarily wired in a switch, relay, and fuse to manually turn on and off fan 1.

Did you change out the cruise control cable? And is your abs lite on.

Yes i had to change both throttle and cruise control cable-they both hook up differently to the t.b.
and yes the abs light is on. I did notice wheel sesors go in differently into the harness but i was going to work on that after i get everything else working properly.

1998 gp and 2002 gps engine harness connect differently to the wheel speed sensor wiring.

Originally Posted by BillBoost37

Do you have the schematics on both engine wire harnesses where they connect into the relay center? That's likely most of the problem. 3.1 probably put a pin in a different place.

Also...if you put an HD diff into a non hd w body trans, the gear ratio is going to be 3.29 instead of 2.93. That might piss off the pcm and cause cruise and abs to not work.

So if i put the std diff back in the pcm will not throw the code for incorrect gear ratio, otherwise i would need to swap the gears a chain behind the valve body?
Also not having any luck finding schematics for between relay center and firewall.

Anyone know or have info on re-pinning wires on the three plugs that bolt on underneath the fuse /relay center?
I found the stumbling problem which was a loose hose between fuel pump and sending unit.
The engine runs great other than the temp gauge not moving off of 0, the low coolant light comes on as the service engine soon light, low oil level light comes on in reverse-third and first, the range selector indicator does not work at all, and fan 1 does not come at all. Any help or info or where to look would be great its been aggravating not finding any info about this.

I'm not getting any responses about my engine harness / fuse relay center questions to fix the dash cluster warning lights and gear selector lights not working right yet. To early for responses or would picks of items in question help get better responses. I really cant believe that no one hear hasn't swapped out a 2002 SE LG8 for a 98 L67 besides having both complete cars.

Have you gotten pinouts on both the current car and the donor? Gm likes to change around for the hell of it. The cutting out could b from the wrong gear eatio, ask me how i know

I do have both
i put the 4t65e-hd diff and axle into the 4t65e trans what else in the trans needs swapped for gear ratio?

Just curious, why didnt ya just use the complete 4t65 hd from the donor?

Originally Posted by JimSWylie

I do have both
i put the 4t65e-hd diff and axle into the 4t65e trans what else in the trans needs swapped for gear ratio?

It was fried with 300,000+ miles on it tore it down clutches and sveral hard parts wasted

Kinda sucks for me i want to get a tuner but cant yet and i have no way in my area to tune it.

And the engine was still good enuf to b worth swapping?