My 93 940 SE turbo has developed a misfire at high rpm that, has become worse. The initial symptoms was misfiring at just past 3k rpms. The misfiring has recently become worse where the car feels like it runs out of power and feels like it's going to misfire or stall not much past 40km/h in second gear (auto) . It also expels some black smoke at the higher revs. At idle, it revs okay though.
I've changed the spark plugs and ignition coil to no avail. My next step is the spark plug leads. I can't find my multimeter and am reluctant to buy one in case my one turns up so I might as well get around to changing the leads anyway. I was wondering what leads I can buy at super cheap auto for the 940? Any part numbers would be appreciated.
In case the new leads don't work, where do I look next to diagnose? Has anyone had problems like this with the b240ft engines? I don't think it's my turbo going south as I hear no whining noise or anything out of the ordinary. I'm going through the hoses but it's hard as the car is sitting at my folks place.
If it's running rough and rich. Yes plug leads will help. But I would buy bosch ones online or from a volvo workshop or even bursons. Though bursons may not bosch brand. EBay is a good choice too. Leads only last 80, 000km or so anyway.
The other issue could be the air mass meter. Disconnect it and if the idle doesn't change much and it runs just as rich it's an easy sign that it has failed. Combined with the lh 2.4 test light connectors.
check dizzy cap i had similar problem...