200Q 20vT + VAG-COM = Driveability problems?

[Grant Lenahan]

Is there a solenoid on the wastegate? Check it.

I think Huw's sniffing down the right path.

Fortunately, I have gained little practical experience here....

Grant
On May 3, 2007, at 8:38 PM, Kneale Brownson wrote:

> Taking this to the 200q20v list for more experience.
>
>   In reply to Huw, there indeed are more complicated controls of the 
> wastegate, including the waste gate frequency valve and turbo bypass 
> valve, along with input from the ECU and from the various sensors on 
> the engine.
>
> Huw Powell <audi at humanspeakers.com> wrote:
>
>> Had a little issue on a 200q 20vT this morning, so I plugged in the
>> VAG-Com to take it for a spin and watch the data. Trouble is that the
>> car was barely driveable, kept hitting the overboost cut out and
>> overall running like sh!t.
>
> Is it actually overboosting? Your wastegate may be stuck closed. Tons
> of power, but too much. Mine (on an 83 5kt) used to freeze shut on
> really cold mornings, for just a few seconds. Wheee, 0-60 at 2-2.5 bar
> was fun.
>
> That wastegate eventually was stuck closed for a while, very difficult
> to drive and then stuck open, making the car a bit of a dog.
>
>> Funny enough after unplugging the VAG-Com and cycling the key the car
>> ran perfect - the issue I was trying to diag went completely away.
>
> Interesting. Now, on your car, the wastegate is controlled by "things"
> other than simple exhaust pressure, right? Could one of them be 
> sticking?
>
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