running fine,then bucks
Asked by YogiMeier Jan 17, 2012 at 05:57 PM about the 1997 Volkswagen Passat 4 Dr GLX V6 Sedan
Question type: Maintenance & Repair
Hello,we have a 1996 Passat 4cyl. It purrs like a kitten,but after 10 or 15 min. it bucks like crazy.The refs go up and down with some back-fires.We installed new plugs, wires,fuel filter,fresh gas.(even added gas-treatment).Any ideas???
3 Answers
Hmmm....a clogged catalytic converter might be the culprit... but, backfires are uncommon unless there's a serious overage of fuel in the exhaust. I would check the CAT first...then look for an injection issue.
Does the bucking and messing about continue or clear up? In 10 to 15 minutes the engine would get hot. I would guess at a sensor failing and delivering a very rich mixture, over-fuelling would cause all of those symptoms. Get it on a diagnostic computer with someone who knows how to use it.
1996 Passat should have an OBDII computer (on-board diagnostic). IF you had a sensor throwing a code, you would have a light on the instrument console. A visit to a diagnostic center is a good idea.
