i've just done the head gasket on my S2 RST and on tickover its perfect,pick up the revs and its still perfect,hold it at 3000rpm and still perf!! BUT as soon as i drive away it misses(well sort of fluffs actually) it has new plugs,new 10mm race leads,new cap and rotor arm and the dizzy is only 8months old.Doesnt seem to be an air leak and the vacuum reading on the boost gauge is pretty constant!! any ideas

 

are plug gaps correct ?

 

think so,25 thou

 

try a spare coil.

 

Also Check:

A) Air flow flap doesnt stick.
B) Ecu pipe isnt crimped somewhere.