Mystery3B problem (long)

[John Larson]

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