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Discussion Starter #1
Cleaned the TB with teflon safe TB cleaner and brush and removed carbon deposits, sludge, etc. After re-assembling, car started fine but now idles up and down. Drives fine with no boost leaks, etc. Threw a CEL (intermittent idle RPM).

Drove to Schmove's Garage (Thanks Ed) and got the codes cleared and did the TB adaptation and still the idle flutters. We removed the air intake hose from the SMIC and the idle went to a steady 800 rpm. No CELs.

Put the hose back and back to fluttering idle. What gives? :???:

Can anyone check their AEB throttle cable and see how much slack there is by pushing down on the cable next to the TB cam. (Engine Off Please).

Thanks!
 

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Mine shuttered too and the dealership said that my throttle body idle gears were worn. Maybe that's your case too???

Jonathan
 

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Discussion Starter #5
Sharky said:
Sure you put everything back correctly???
Yup!

The funny thing is when the headlights and other accesories are on, the idle is perfect around 900 rpm and steady. So when the alternator has a load, the idle is smooth. This tells me the servo motor/gear that moves the plate (throttle position) is working and not worn out.

It may also mean the problem is electrical i.e. the voltage on the TPS at idle, etc. Does anyone know the pin position / schematic of the TPS connector? Is this available from Haynes, etc.?

Sharky?

I'm tempted to open the TPS and check the contacts on the slider. Some gunk could have seeped in there. :mad:
 

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powerslide, how long did it take for the ECU to smooth everything out? Do you remember what the DTC you got was? Kinda having the same problem and I have a CEL too. The CEL comes on after driving for about 15-20 minutes and under load.
 

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Discussion Starter #9
vwfool2000 said:
powerslide, how long did it take for the ECU to smooth everything out? Do you remember what the DTC you got was? Kinda having the same problem and I have a CEL too. The CEL comes on after driving for about 15-20 minutes and under load.
It took longer than expected. I'd say about 60-80 miles of driving ( 2 days of running around). It settled down nicely and really now is smooth and I can feel my butt move at WOT. :lol:

As for the DTC, we didn't save it although it says it is = to intermittent idle which really what it is. Good luck.

BTW, when it is fluctuating at idle, turn on the A/C and see if it goes down. Do this time to time and I think it will help the ECU learn it again. I believe you and I really cleaned the hell out of the TB and the valve because others didn't have this issue. My TB looked better than new after I was done with it. :wink:
 

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OK, I guess I will give it a couple of days. weird though that when I first started it up and drove it it was rock solid. then after 20 minutes and at 70mph the CEL came on. but when I slowed down at a light it was at 900 and solid. when I stopped at work and put it in Park is when the fluctuation was happening.
 
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