You changed your spark plugs on your Volvo 01 s6o and it is still misfiring Also changed coils and fuel injectors any suggestions you heard vacuum leak how do you check to see if that is it?

wiki answers should really put a posting date on this stuff... I am having same trouble with my v50 t5 - get someone with a vida system- diagnostics it will indicate which cylinders are misfiring and part of the numerical code given may give a hint as to the cause of the misfire. if there is a pattern to the misfire eg. 3,4,5 it could be the wiring to the coils ie. a dirty earth on that wiring set. A simple thing to check a weak point in all volvos in the fuel cap - it's cheap and very important to fuel pressure, which can also be cause of intermittent misfires - however would suggest errors for fuel pressure may come up on the mechanics vida system if it is fuel pressure problem eg fuel sensor low pressure etc..