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Discussion Starter #1
Ok, so I took my TB off a couple of days ago to clean it. It had been idling in the 600rpm range.

Ok, so I'm taking it off and cleaning her up all nice and pretty, but realize that it's hard to get the edge of the butterfly valve and right there in the corner where the valve meets the...um...valve holder thingy. So, I take the valve out. Much better, i could get the edge clean and fit my toothbrush where the holder thingy meets the tb housing. ok..good. So I get ready to put the valve back in when I notice that there are small recesses on the perimeter of each side of the valve. which way do they face?? I took a guess and put it back together...start the car and it's not idling at 600rpm anymore.....rather at 1200...doh! I unplugged the ECU and did the whole reset deally, but no dice. It's been 2 days now and still the 1200rpm
Ok, first question. Does anyone know what I'm talking about when I mention those grooves on the butterfly? If so..does it matter how they're oriented in the TB?
secondly...if it doesn't matter..why is my car idling so high now? TB adaptation in order?
thirdly, I noticed that the valve doesn't close all the way. There's a slight opening. Should it be like that or should it make a complete seal?

thanky!
 

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The throttle body plate should rest at 3 deg. for idle. Not sure if high idle on our cars is indicative of a vacuume leak but that's my first guess.

Be sure you got that hose clamp on tight, and you did use a "new" gasket for the TB-to-intake manifold, right? All electircal connections on tight? You didn't accidently remove the IAT sensor or disonnected it's electrical plug?

Just some stuff to double check.
 

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Discussion Starter #4
Um...well, the gasket was not brittle nor did it stick to the TB, so I cleaned it and reused it. :lol:
The IAT was the only elec plug on the TB right? If so, I connected that when replacing.

I would think that if there was a leak it would run like crap when on boost. It doesn't. Only prob seems to be high idle.
 

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i would try to put your key in the ignition and turn all power on so lights light up. this will auto alight your TB i believe. leave it like this for 2 min or so and see if that helps. I know i was made to do this when i got my chip, this does somethin to the TB
 

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Discussion Starter #6
Did that last night... no go.

next!

;)
 

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mine did that for 2 days after i cleaned it, after about 500 km's or so it worked normal. id leave it for a little and see what it does :???:
 

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you may very well have the flapper on backwards.
iirc, the valve has a bevelled edge to help "seal"
with inside of the throttle body. so, just reverse it...

if you run the engine at 1200rpm too much, yer
gonna run the risk of killin yer tranny :wink:
when you put yer throttle body back together,
just use a VERY thin layer of silicone sealant
on all surfaces of the gasket. who needs to spend
money on gaskets anyways :crazy: :lol:
 

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Well, not sure if this will help, but had a similar problem on my wife's 1990 Toyota Cressida. Decarbonized the engine and cleaned out the TB and the engine was suddenly plagued by a very high idle. Turned out that the cleaner had gummed up the TB position sensor and the computer didn't know it was supposed to be idling. Sensor had to be replaced. May not be the problem here, but sounds similar...
 

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Discussion Starter #11
I'll try flipping the butterfly valve and report back!

FYI, I used Vavoline synthetic carb and TB cleaner....seemed like glorified mineral spirits..
 

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According to Bentley you need to do a full TB adaptation if you remove/reinstall the TB (find a vag-com).
 

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man i never did the
full TB adaptation if you remove/reinstall the TB (find a vag-com).
on miune and it worked perfect after 500 km's of driving :???:
 

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CB said:
Well, not sure if this will help, but had a similar problem on my wife's 1990 Toyota Cressida. Decarbonized the engine and cleaned out the TB and the engine was suddenly plagued by a very high idle. Turned out that the cleaner had gummed up the TB position sensor and the computer didn't know it was supposed to be idling. Sensor had to be replaced. May not be the problem here, but sounds similar...
Thats exactly what the VW tech toldme when I purchased a can of the Throttle body cleaner, I have a 2002 and didnt expect the throttle body to be that dirty or gummed up, I used the cleaner anyway, I did not remove the assembly itself. The tech told me to be careful as the cleaner can ruin the sensor. You might have that problem now. Although I freakedout because when I cleaned the throttle body as soon as I started the car it idled at 1200 rpm but after 2 mins it bounced down to 800 rpm. Now it idles perfectly. Good Luck. If I were you I would seek help from a VW tech. You might have clobbered the sensor.
 

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Discussion Starter #15
Grrr... Looks like its time to invest in a cheap laptop and vag-com.
 

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Discussion Starter #16
Ok, I flipped the butterfly valve, now it's idling higher... around 1600 RPMS. :mad:

I think it's my throttle pos sensor. I assume you can replace only this part and not have to do the whole TB assembly. Has anyone had to do this? How much was it?

Also..will the TPS from the V6 work on my 1.8T?
 

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how do u avoid hitting the TPS??? i never heard of this prob b4 now........
 

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ChkYaHead - Do a vag-com TB adaptation before you spend any $$ on replacement parts. The vag will also indicate if its the TPS or some other failure.
 

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Discussion Starter #19
I don't have access to a Vag-Com...can a TBA be done with those generic OBD tools regular mechanics have?
 
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