I had a 93 evc and it did the same thing . The dealer couldn't fix it as he
said he had to see it happen . I gave it to them for a week and still no help
as i drove it away from the shop it happened again ,I was so disgusted I
started looking myself even tho it may have voided the warranty.I think the
problem left after i replaced the o2 sensor.I learned to turn the switch off
and on while running down the road after awhile it would clear up.There was
bulletine issued by vw that said it could be the contact on the ayr folw
meter that was momentarily losing comtact.
