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

[cody at 5000tq.com]

Quoting Huw Powell <audi at humanspeakers.com>:

>
>> 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.
>

It only overboosts when connected to the vag-com, any other times it  
runs ok. It was running really rich (to the point of random  
mis-fires), which is why I wanted to watch the sensors while driving,  
but other then that it ran fine before and after connecting the  
computer. Going on that I'm going to say it's unlikely the wastegate  
was stuck.


>> 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?

This 200 is 100% stock, with the N75 valve and such exactly OEM.  
Possible that the N75 was stuck, but would be a huuuge co-incidence if  
it onl;y stuck when the vag-com was plugged in and never before, never  
since.

-Cody Forbes
http://www.5000tq.com