Mystery3B problem (long)

[Ben Swann]

How far off - one tooth or more.

Ben 

-----Original Message-----
From: John Larson [mailto:j.d.larson at verizon.net] 
Sent: Monday, December 20, 2010 3:22 PM
To: Ben Swann
Cc: '200q20V mailing list'; 'alan cordeiro'; quattro at audifans.com; qshipq at aol.com
Subject: Re: RE: Mystery3B problem (long)

On 11:59 AM, Ben Swann wrote:
> My main suspicion at this point is that the two cam sprockets are 
> mis-aligned and the head is not breathing properly.  Owner says that 
> should not be a problem because the head would have been re-assembled 
> properly, but can not confirm the work.  He insists the main belt is 
> correct w/respect to the crank.  His reasoning the sprocket theory is 
> not valid is that the problem occurred before the head was rebuilt. I 
> have the gut feeling that whoever put the head back together used the 
> 16v mark(s) on one of the sprocket instead of the 20V mark and just 
> copied the mistake that had been made previously.  If I recall there 
> are different marks for different heads, but the same sprocket is 
> used.  I have seen enough other things that were not correct, namely 
> the sensor connectors installed on the wrong devices, that I won't 
> trust that whoever installed the head, did it by the book as they did 
> not bother to look at wiring diagram to verify sensor wires/colors were correct.
Ironically this is a case where Audi did not use idiot-proof connectors to ensure that
the three sensors in same proximity could not be hooked up improperly.
>
> I can of course verify all this speculation, but will not touch the 
> car again until assured whatever service or diagnostics I'm doing is 
> not going to be for free.  I already went beyond what was expected, 
> found and resolved several problems using up an additional day of 
> "free" time cause I'm a "nice" guy.  Right now I'm just looking for 
> options to present to the owner with greatest probablilty of success for amount of
time spent.
>
> Does the mis-aligned cam sprockets sound like it is the most likely 
> culprit at this point based on all the other things I did/verified? What do you think
Scott J?
>
> Ben
>
I'd sure be tempted to look at the cam timing. I've seen misaligned cams make a 20v not
rev.  Pretty easy to see with the cover off.

John