I bought a 2001 Acura TL with 135k miles on it, 3.2L. The shop I bought it from told me it only needed a transmission, had to pick it up on a dolly and when I got it back home the gas light went on. so I bought a trans and installed it. The car moves fine now, but has a hard shift from 1st to 2nd, and 2nd to 3rd. More issues arose before I ever had the chance to put this thing on the road.... now the vehicle wont recognize the correct gear on the dash so it doesn't want to start. The shift lock doesn't activate to allow me to shift it either. There was an intermittent misfire that seems to have fixed itself. I am a mechanic and have been for 11 years so i did the tests. pulled out the fuel pump tested the level sensor, that all tested good and the wiring had continuity back to the instrument cluster. So then I started testing for the shifter issues. Ruled out the basics, brake switch, TP sensor, shifter assembly (acutally replaced it twice to quickly verify that wasn't the issue) tested and swapped transmission range sensor with the old one from other transmission.

After all of this I brought my TL to the acura dealership and said this one is beyond me and probably needs a PCM that I dont have the pass-through device to reprogram. They made me sign off on 3 hours diag at a reduced labor rate (420$) I told them not to touch my car without the mechanic calling me to know what I have done so far. They finally called me back a week later and said I need to pick up my car. Outraged by their neglect for my own request and them swapping out the brake sensor without my permission they tell me 380$ is the total and that the fuel pump, shifter assembly, and transmission range sensors that I already ruled out need to be replaced, but they as an acura dealership will not fix it. After some calm talking to them and asking why an acura dealer wont fix an acura vehicle I finally got to the service manager who raised his voice and I got loud so I ended up with my car back for free.

So I brought my car back and used a self tapper screw to hold shift lock down, put a push to start button on the dash so I can always start it. Now it runs and drives just fine, but I still dont have a gas gauge and there is still a hard shift from 1-2 and 2-3. If anyone has an insight on what I need to do to fix these issues it would be greatly appreciated. Would love to remove the self tapper and push to start too if possible. The codes I am getting are Engine: p0700 (standard code set for a transmission fault), Transmission: p1706 (A/T range switch open), ABS: 31-2 (pfinh signal failure), 34-2 (TP reference voltage failure), 61-1 (battery voltage failure). Thank you to any and all input on my behalf.

 

Welcome to AZine, Dylan_Gee.

The interlock is pretty straightforward electrical diagnosis, as the circuit is pretty simple. You should probably get an electrical troubleshooting manual so you can follow the wiring diagram back from the interlock.
The gas gauge is also a simple circuit, and you're probably missing a ground somewhere. Again, you'll want the wiring diagram for it.

The misfire honestly isn't a priority until everything else is sorted out.
The best case scenario for the other codes is missing ground connections, but we don't know the condition of the car before you bought it. If there were no codes before the transmission swap, then it seems like you did a poor job with transmission replacement and wire harness. What car did you source your transmission from?