Misfiring Problems

[JASPBE]

Got a Vauxhall Vectra that recently started to misfire and jugg along, soon after there was a foul smell of
rotten eggs inside the car. Local garage replaced spark plugs to solve the misfiring problem, and also said that the foul smell was probably down to the catalystic dumping its gases, which they said happens from time to time.

Today the foul smell has gone but car still misfiring when travelling at 25-30 mph - was it a spark plugs problems or something else that was missed?

Any suggestions?

[Mavis22]

I'd guess lambda sensor has gone (do you have any management light showing?) causing the fuelling to be wrong. Get it checked out sooner rather than later, or you'll need a new cat.

[dougielogan]

9 times out of ten it will be the coil pack failing, did your garage not give the car on a diagnostic check? If not change your garage!

[gouldc]

Agree with Mavis - the smell of rotten eggs is usually associated with a failed/failing cat.

This may not necessarily be the cause of the misfire, but is certainly going to be associated.