TPS Checked - Now what?
 

So here are the symptoms I've been experiencing lately:

My transmission has had an aggressive 1-2 shift at very low rpm's (traffic speeds) and an occasional flare between 1 and 2 as well. It's never worsened in my 3 years of owning the car. I usually bypass it by using manual mode to shift between 1st and 2nd at the right rpm's instead of what the car thinks is right.

Car hesitates when it's cold outside and the engine is cold. Seems like the throttle is dead until 1500 rpms. When it warms up, it's almost completely gone.

As soon as the weather started to warm up, I've had a rough idle. It was similar to when my O2 sensors went bad, like pulsing, only not as violent. It stalled me once at a red light but it was freezing out and I had just started the car. If I turn the A/C on low to raise the idle from 500 to around 700, it idles smooth as butter. I've just been leaving the A/C on low and haven't noticed it.

I am going to Subaru tomorrow to get a coolant temp sensor, because it can't hurt.

Today, I went to go check the TPS to see if it was in spec. I didn't check anything with ohms, just voltage. I hooked up my multimeter to the battery to make sure I had it on the right settings and it worked - 12.25 volts. Good to go. Finally got the needle to pierce the wire at the TPS and hooked it all up. Got a reading of 0.50 volts. Exactly in spec. Just for the hell of it, I adjusted it to .45 volts. No significant difference. Adjusted it to .70 volts, and it seemed to help. It didn't remove the hard shift, but it definitely softened it. Idle seemed to settle well too. Came back and adjusted it one last time to .55 (just to keep it in spec). Idle seems to level out. Drove it for a little, shift wasn't that terrible. Put it in park, and it would level out at about 1100 rmps. I think it's because the car wasn't hot yet, but it could have also been due to me adjusting the TPS. Turned the car off and left it at .55 volts.

So, where do I go from here? I'm already buying a CTS, but should I buy a new TPS? It honestly did not make a huge difference like I thought it would. Car doesn't seem any more or less responsive. I couldn't test the hesitation because it's warm out. I don't want to buy a new TPS and have it be exactly the same. :o

P.S., I have OT's aftermarket transmission resistor in, so it's not that. Brake band? Gimme answers! :p

Re: TPS Checked - Now what?
 

I've had sort of the same problem, changing the 02's made it better but I think the MAF may be the main culprit, i cleaned it which made things much better but it came back.

Re: TPS Checked - Now what?
 

I just changed my O2 sensors about a year ago, so it's not them. Do I just clean out the MAF with an electronics cleaner or should I use compresses air? The coolant temp sensor may solve the idle for me though. It was very intermittent today.

Also, when I was adjusting the TPS, it sometimes made a buzzing sound, does that indicate anything?

Re: TPS Checked - Now what?
 

Just MAF cleaner, no compressed air.

Re: TPS Checked - Now what?
 

Update: surging idle is back.

Should I replace my TPS anyway? I have someone that is willing to sell me one for $75 that's functional. Is there any way to determine it's bad without taking it off and testing the ohms?

Re: TPS Checked - Now what?
 

taking it off and testing the ohms seems like the easiest way.