Is this normally while idling at normal running temps.

[Spencer87]

http://www.youtube.com/watch?v=SJqKTJxPm0s

So when I'm idling, some times it does it a lot more frequently in shorter bursts, other times it doesn't do it at all.

You can barely make it out, but the rpms slightly rise.

Anything to watch out for/check?

[trickey1991]

I've heard it can be your TPS ..but i dunno..mine was kinda doing that..then i adjusted my TPS and now its fine

[bobbo]

If that's the only problem you're facing I'd say you have nothing to worry about.
That being said if you're asking tech questions you should include any and all modifications.

[Spencer87]

Ok - I'll look into the TPS further.

Practically stock (I haven't done anything to the car), still learning what I have. From what I gathered, it was slightly lowered and had an upgraded exhaust but other then that, I don't think anything has been done.

I wouldn't say I have problems, but I wouldn't say its running perfect either. Its been running 100% better since cleaning/resoldering MAF but it still idles weird sometimes and there's times at low RPM that it makes like a pop sound (I usually notice it when Im rolling and start in 2nd - I just slow down a little more and start from 1st to prevent it from happening).

[trickey1991]

I beleive the wire going to the TPS needs to be between .48volts -.50 volts at idle

[Skym]

If R33 TPS it should use a voltage for idle contact instead of a idle contact pin inside stock R32 TPS.

Easy way to check TPS is load engine up with light's, aircon, etc and move car forward. The first thing you should notice is engine struggles to idle (ECU doesn't use idle tables, as doesn't see idle contact). Loading engine up on a steep hill with aircon, etc on is another way to check.

Slight idle rpm fluctuation is normal (idle stabilsation tables adjusting to airleaks, etc), adjusting to aircon being on, etc.

Another cause (had this problem on my car) is faulty o2 sensor making revs rise when it makes engine leaner and revs drop when it makes engine go richer. Also if left long enough, engine can run rich, spit flames (if there's no catylitic converter) when you back off throttle (popping sound from exhaust).

To test if o2 sensor is faulty -

Hold at 2000rpm and should notice o2 sensor voltage fluctuate from 0V (lean) to 1V (rich) and then from rich to lean. Should do it in I think was around 5sec or so one way. If slower than that, o2 sensor is stuffed. It helps if you have a turbo timer or similar to display o2 sensor voltage or multimeter at 02 sensor or ECU plug.

[gtrjerry73]

my car does this too occasionsally apparently with these older cars maybe the ecu's arent as efficient when they are getting on in the years but i was told that your ecu will cycle and check all your sensors and sometimes it does a retest if it missis something. kinda doubles back and retests a sensor. its a split second but will make your idle kinda "miss" like that. i was told its nothing to worry about unless it starts to happen constantly all the time and for longer periods of time. no idea if this is what it is but it looks exactly the same as what mine does.

[gtrjerry73]

oh and its not vehicle specific either apparently alot of older cars will do this

[Spencer87]

Ok cool - yeah it will still be a good idea to check my TPS and o2 sensor but yes, that is what I was looking for. I plan on changing my MAF/ECU next winter (as well as a few other performance related items ) so I just wanted to see if I could hold off until then and just do some TLC this summer.