Do a compression test.  Sounds like a burn valve.
                  Eric

Peter Pollard wrote:

>Hi all my name is Peter. I live in Australia and recently purchased a 92
>syncro transporter and have a engine miss. The van starts fine and runs
>smooth for about 40 seconds then the revs drop and the miss kicks in. The
>miss in like in a cycle every 2 secs. have replaced cap, rotor, leads, 02
>sensor, cleaned and tested idle stabilizer, adjusted throttle switch, new
>air and fuel filters, capacitor fix on air intake and had fuel injection
>cleaned inline.
>the only things left to do is temp sensor 2
>Man I want a digi tool lol !!!
>If any one can help and Aussie please let me know.
>All the best SyncroPete.
>PS great site thank you all.
>92 VW Transporter Syncro.
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