[Christ]

I still haven't been able to find the diagnostic flow charts for the P1640 code, and the P0105 is showing up, which is MAP/BARO CKT Malfunction, basically saying that there's something wrong w/ the MAP, but the system isn't sure what.

I replaced a TPS that only showed NOT or WOT, and a huge dead spot in between, and that didn't fix the problem.

The TPS at closed throttle still reads 18-20%.. And it's not technically adjustable, although I probably will adjust it anyway, by slotting out the holes for the screws.

Coming down the hill in 1st gear, engine braking at 4k RPM, I get around 8 inches of vacuum coming from the MAP sensor... I know this is wrong, it should be damn near 30 inches. I've tested for vacuum leaks, but it's kind of hard to test correctly when you can't test under load... The voltage input is fine, signal output is fine, and I haven't checked the ground for continuity back to the PCM yet, but I will check that as well.

It doesn't feel like it's actually braking though... the car still feels like it's trying to accelerate, or like it's keeping about 1/4 throttle. I know that MAP codes show up for things that aren't directly related to the MAP sensor, so I'm checking other stuff as well, such as the IACV and TPS settings.

Anyone know how to adjust the IACV?

I posted over on Saturn Fans, but they're not much help...