Recently the 940 has started running a little erratically - first noticed when idling in traffic; engine starts wavering (revs slightly up then slightly down), never stalls though. Calms down when put into neutral or park. Also started misfiring, most obvious when you ease off the gas at mid speeds and misfires under load (especially cornering or climbing); cruises fine though.

Only other related problem might be engine temperature sensor - guage is reading incorrectly (reads cold for too long, then goes to the middle but occasionally reads cold again), checked thermostat and that's ok.

My other car's a 240 with B230A Carb engine and pretty straightforward. This one's a B230F with engine management/FI etc, and I'm relatively new to that side of things, so a few pointers would be useful (the FAQ is very useful but not sure where to start).

Thanks

Neil