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Discussion Starter · #1 ·
So i cleaned my throttle body a couple days ago, and i was driving this morning and knowticed that when i went over 2k rpm, there would be a vibration throughout the whole car.

I dont know what this can be as all i have done is the throttlebody, i checked and it is on tight. When i did the throttlebody, i accidently forgot the rpm position sensor , could this be the culprit?

Ideas?

99 Passat GLS 5sp 67k miles.

Ill drive it later, mabe it was just a morning this and it was warming up?
 

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Give the engine computer a couple of days to adjust to the new airflow characteristics before concluding that something is wrong.

When I installed my turbo timer I had to disconnect the battery. The car ran like shit for three whole commutes to-and-from work. Then, all of a sudden, it was fine. Literally, like it had been observing and collecting data for three days and then suddenly put all of that observation into practice, and the car ran just like it used to again.
 

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Discussion Starter · #3 ·
Give the engine computer a couple of days to adjust to the new airflow characteristics before concluding that something is wrong.

When I installed my turbo timer I had to disconnect the battery. The car ran like shit for three whole commutes to-and-from work. Then, all of a sudden, it was fine. Literally, like it had been observing and collecting data for three days and then suddenly put all of that observation into practice, and the car ran just like it used to again.
alrighty, yeah the day i did it it was raining and i couldnt really "test" it.

Would a cracked DV do this? When i rev the motor, by pushing the throttlebody open, and listen it revs to 2k, where turbo spools, then i hear a semi-faint PSST/SWOOSH like sound, like a BOV.

BTW: The car seems faster now and more responsive!!! Its great!
 

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alrighty, yeah the day i did it it was raining and i couldnt really "test" it.

Would a cracked DV do this? When i rev the motor, by pushing the throttlebody open, and listen it revs to 2k, where turbo spools, then i hear a semi-faint PSST/SWOOSH like sound, like a BOV.

BTW: The car seems faster now and more responsive!!! Its great!
To be perfectly honest, I have no idea what causes the vibration. I had it too, when I tested my car after cleaning the throttle yesterday. I couldn't feel it today.
 

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Discussion Starter · #5 ·
Well, it makes me feel a little better im not the only one. We will see what happens in the coming days. I was/am gonna be replacing the stock DV anyway so we will see what happens
 

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Do you have a throttle cable? If you do, make sure your kickdown sensor is plugged in so the ECU can tell when you've opened the throttle all the way (this is required for calibrating the throttle position sensor). Then turn the car on, but don't start the engine, and press the gas pedal to the floor (making sure to engage the kickdown switch) a few times. Drive the car around a bit and make sure the throttle feels right, then unplug the kickdown switch again if you don't like it.
 

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Discussion Starter · #12 ·
Do you have a throttle cable? If you do, make sure your kickdown sensor is plugged in so the ECU can tell when you've opened the throttle all the way (this is required for calibrating the throttle position sensor). Then turn the car on, but don't start the engine, and press the gas pedal to the floor (making sure to engage the kickdown switch) a few times. Drive the car around a bit and make sure the throttle feels right, then unplug the kickdown switch again if you don't like it.
yea i do. whats a kickdown sensor and where is it?
 

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yea i do. whats a kickdown sensor and where is it?
It's built into the rubber bung that holds the throttle cable steady as it passes through the front firewall. (there are two firewalls, and the battery sits in between them.) Unplug it by squeezing the wire clip TOWARDS the plug body and pulling the plug off the sensor. As always, installation is the reverse of removal. :)

Anyway, the kickdown sensor only activates after the throttle has been pulled completely open, and it serves to boost acceleration by forcing the transmission to shift into the lowest gear it can safely shift into and stay there until the engine redlines.

Personally, it bugs the hell out of me and I had it unplugged, but after I cleaned my throttle body I realized that the kickdown switch is the only independent verification the ECU has that the throttle is actually wide-open. (sure, it can assume the throttle position sensor is aligned correctly, but the kickdown sensor CAN NOT MOVE unless the throttle is wide-open, so it's proof-positive.) So I plugged it back in for my recalibration.
 
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