Runs fine, then lopes itself to death.

[1RedPrix]

alright, so my 98 gtp will run fine for about 10-30 seconds, then it starts loping, gradually (but quickly, within 30 seconds) gets worse till eventually (minute or two) it lopes its self harder and harder till it dies, the IAC continues to open this entire time. replaced the MAF, TPS, IAC, fuel pump, fuel filter and FPR. It did this a few weeks back, and I replaced the FPR, it was fine for a week or two then it started acting up again. I checked for vacuum leaks, its throwing a TPS Voltage Low code (4.2V at WOT same with new and old sensor) P0122 and a P0452, but when I check for vacuum leaks there isnt any. Little help here guys. Im lost and dont have any more money to throw parts at it till its fixed.

[99GT2dr]

http://www.obd-codes.com/p0122

What is making you want to look for vac leaks?

[1RedPrix]

Because when I check the TPSes center wire with a volt meter its fine. No dead spots, and the sensor is brand new. 4.3V at WOT, 0.2V with the throttle untouched.

[99GT2dr]

Apparently the pcm disagrees with the TPS being fine, hence the p0122 code. Did you try checking the stuff mentioned in the link? Just because the sensor is putting out the right voltage, doesn't mean the pcm is seeing it.

[1RedPrix]

Absolute throttle position is between 0 and 0.4 PERCENT at idle when it does it, but higher when its running fine.

[1RedPrix]

update: front o2 sensor was bad, unplugged it, car ran fine. New part will be here tomorrow.

[Uno99]

Do you have a way to check the fuel trims. If they are way off it could cause some issues there as well.