2200rpm idle while driving home, help!

**B5Burn** · 05-31-2008 04:09 PM

I was only out for a quick drive... I think it occurred as I downshifted coming to an intersection, but I could be wrong.

Drove for 30 mins or so, pulled over and idle for about 2 minutes, no problem..I did a full throttle 3rd gear run (well only to 110kmh limit) a cpl miles before that and I am positive my idle was fine then, I pulled from a standstill. I was shifting slowly as I was in moderate traffic once I got up to speed... downshift to slow down at intersection and 'hey wtf?' My idle was up to about 2200rpm.

It would hit 2200 and then drop down a hundred or two... sounded like it was doing it in steps and then it pops back up to 2200.... drops and continue with that pattern. Felt like my boost dropped too, but I limped home for the cpl blocks so I didn't push it to really find out.

I reviewed all the hoses and fittings and everything seems fine (have not done a pressure test and I have downloaded the pressure tester DIY), my car has extremely low miles and all upgraded blue hoses. All fittings are solid.

Help! Ideas or any suggestions welcome.
Bill.

**Ewok_Fetus** · 05-31-2008 04:33 PM

Sounds like A) Your throttle doesn't return all the way or B) You have a leak after the throttle body...

**B5Burn** · 05-31-2008 05:14 PM

That's what I thought, A) but I checked the throttle action.. Hood open, pedal up and down with my right foot, I could hear it tapping the stop when it came back up. B) Can you clarify for me here? as in, anywhere on the motor? or physically right after the TB?

Thanks.
B.

**legionvr6** · 05-31-2008 06:40 PM

try cleaning the TB and doinf a TB adaptation with vag-com

**B5Burn** · 05-31-2008 07:05 PM

Thanks, looks like my next step... I can't find a TB cleaning DIY though... is it as simple as taking it all apart, spraying some carb cleaner or something and then reassembly?

B.

**Ewok_Fetus** · 05-31-2008 09:12 PM

Originally Posted by B5Burn

Thanks, looks like my next step... I can't find a TB cleaning DIY though... is it as simple as taking it all apart, spraying some carb cleaner or something and then reassembly?

B.

It is very easy... You can do it taking it off or without... Just watch your fingers because the throttle plate likes to snap back... Hard... I would use throttle body cleaner and not carb cleaner... Just follow directions on the can!

**B5Burn** · 05-31-2008 09:29 PM

THANKS, appreciate the help. Guess I know what I'M doing tomorrow!

B.

**andyrew** · 06-01-2008 02:20 AM

Another idea is to take throttle body cleaner and spray it around the intake piping (couple of quick mists on connections). Listen for difference in RPM's and that will tell you if you have a leak.

Asside from that, do the cleaning above, make sure you check all your wiring connections as well and tighten those up.

**B5Burn** · 06-01-2008 05:41 AM

Thanks guys. I went over it all with a fine tooth comb yesterday and can't find a single problem with any of the hoses or electrical connections... everything is toight... MUST be the TPS and or the Throttle body as you guys recommend... my neighbours aren't enjoying the time it is taking me to discover the problem... 2200 rpm on a 2.0T with a 3" TB exhaust is kinda loud :)

[edit: forgot to mention the TB]

**B5Burn** · 06-01-2008 03:47 PM

Not a dirty TB. Cleaned it up real nice, it was a tiny bit dirty... but not really. When I sprayed it the revs dropped.. normal or not normal?

Drove around, seems for the most part boost is where it was before the problem...

Bought some brake cleaner to spray on some spots....

When I turn the key to the On position in the ignition (but don't start), should there be a 2 or 3 second long psshshhhhhhhh coming from somewhere under the engine's intake manifold (possibly near the back half)? I don't remember hearing that before... I wonder if there is a air leak in some rear engine point?

Any more ideas? (other than getting vag com on it, which will hopefully be in a cpl days) My neighbours really hate me.

**317ssayzarc** · 06-01-2008 03:50 PM

damn you still havent gotten this licked huh? its hard to help you w/o a log, when you get a chance log the throttle angle and tps voltage

**B5Burn** · 06-01-2008 03:58 PM

Yeah, I am practically on the eve of obtaining the goodies to help, but am shooting in the dark right now. Vag Com on the way, Innovate gear on the way... good summer of driving on the way :)

Thanks for the suggestions guys, I am open to check anything.. kind of a wild goose chase... but it can't be far.

B.