1994 passat-overheating and misfiring

[Spackman]

help. My 1994 passat, 1.8 petrol has a problem. It's fine for about 5 minutes, then it starts getting hotter and hotter. Then it starts misfiring. (bangs come out of exhaust). I've changed the plugs, distributer cap, rotar arm. Is there anything obvious or common place I'm missing. There's plenty coolant.

any help appreciated.

cheers

[boschmann]

Does it misfire before overheating? What about the plug wires? Has the timing been changed? Does the radiator fan come on?

[Spackman]

Thanks for the reply. The temp needle goes up to about half way and then the fan comes on. Think I might have been overeacting. It just seemed alot hotter than when I took it up the motorway and it stayed at about 70 degrees all the way. The misfire could be due to the spark plugs I put in. They were Bosh WR78X super 4's, from Halfords. They seem to have been the wrong length, causing a misfire. I put the old ones back in and there has been a partial improvement. Having said this, the car still misfires if you put your foot down, or if you try to pull away in a low gear. Very jerky and the odd bang out of the exhaust.

Any other thoughts would be welcome.


cheers

[boschmann]

North American models had alot of problems with cracks forming in the ignition coil. Spraying the coil with water exposed the problem as it would start acring. The metal ends of the plug & coil wires were also prone to deteriorate.