mikef

iTrader: (3)

I been having idling problems that spikes up and down when i rev the engine.. sometimes it almost stalls out.
I was unplugging devices to see if it makes a differents and the only thing that stop the low dipping in RPM was this. Can anyone help me what this is. thanks

1JZPWRD

iTrader: (59)

Its the TPS. Throttle Position Sensor.

mikef

iTrader: (3)

Ok thanks, do you think that would cause the low rpm spikes?

1JZPWRD

iTrader: (59)

Absolutely. I would check the resistance and see if it is within specs for starters. If it is, then clean the throttle body and butterfly on both sides. Check for vacuum leaks, and your IACV (Idle Air Control Valve).

Have you tried to loosen this and move it after the symptoms started? Or have you left it alone?

SC400slide

iTrader: (11)

Like Mark said, the TPS. If your idle is spiking and you suspect your TPS, it might be a good idea to set it to spec. There are a couple threads on that too.

mikef

iTrader: (3)

Yeah I tried to loosen it and move it around but it didnt make a differents, I tried to take off the IACV but the screws that hold it on are really tight,

Im not sure how to get it off yet, I did unplug it and the revving was going up and down over and over so I plugged it back in and tried that TPS and it stopped the weird dips,
whats weird is that when I turn on the ac it really dips down almost stalled
Im going to clean The TPS because i know for sure I can get it off

I cleaned the throttle body and it was super clean already

BiGEZ

iTrader: (24)

Might sound weird but it could be your oxygen sensors. I had the same issue after cleaning my throttle body
Replaced the oxygen sensors and the car ran perfectly. You might want to double check your vac line and
connections. Did you replaced the throttle body gaskets when you reinstalled it?

SC400slide

iTrader: (11)

o2 sensors is actually what fixed my SC when it was having issues like this...not really wierd.

1JZPWRD

iTrader: (59)

If you believe it is something further, then pull the codes and see what it is. I wouldnt throw things at the car, unless you can narrow it down.