[s-cars] Misfire Diagnostic Help?

[Chris Hemberger]

Hi Folks - have owned my S6 Avant for ~7 yrs & ck the site from time to 
time; have never posted but the time has come..  My car w/ ~160k has developed a 
misfire/rough running condition that I'm looking for some assistance in 
troubleshooting. Car is stock other than a Stage 1 modded-ECU (MTM as I recall) 
& has had the Apikol coil-conversion for 3yrs; I'm getting a '4411' code 
indicating a problem w/ the #1 injector. Swapped coils around (and even tried a 
new one..), pulled the injector connector and the condition worsens which would 
indicate the injector is functional to some degree - which leads me to my 
question: do the injectors experience 'partial' failure which might explain my 
situation? Selectively disabling each injector on each of the remaining 
cylinders results in degraded operation. Have run out of diagnostic ideas & 
thought I'd come to the experts - any suggestions/questions welcomed!
Thanks,
Chris Hemberger
Amston, CT
'91 200q Avant
'95.5 S6 Avant