My 84 has the exact same problem  It is in the shop today so they can 
try to identify the problem.  I will let you know what they did and 
what the outcome was.

Here is the initial failure report;

AirCare Inspection Report
1984 VW Westfalia, 205,000 kms.

HC@load (ppm) :  Actual:  115  Permitted: 300
HC@idle (ppm) :  Actual:  367  Permitted: 350  FAIL

CO@load (%) Actual 0.91  Permitted 2.00
CO@idle (%) Actual 0.42  Permitted 4.00

NOx@load (ppm)  Actual 1450  Permitted 2667

brian.

> The original purpose of starting this list was because I wanted some
> information on how to get my '84 Vanagon to pass emissions testing in MN. 
> I just got back from the testing station, and it failed again (after
> having passed last year).   The measurement that fails is HC. CO is just 
> fine and CO2 is passable. I think that I can probably get it to pass by 
> setting the idle higher and adjusting the timing.  Any other quickies I 
> should try ?  
> 
> Oh well.....
> --
> Gerry (not looking forward to working on the car in the cold) :-(
> Gerald Skerbitz <gsker@med.umn.edu> U of MN Med School Admin 6-5379
> Home St. Paul,Ramsey County,Minnesota, USA
>