Listening to my Volvo 960 on start up, it appeared to be a cylinder down. I quickly tracked this down to cylinder No 3, so I changed the spark plug and then the coil pack with definitely working ones, but the misfires persists, certainly on tick over. It does seem to run fine at higher revs but that maybe because it all smooths out and I can't then hear it.
I now have no idea where to look next so any help or suggestions would be appreciated.
This is the first time I've needed to do any engine work on this car since I got it two years ago and unlike my 20 year ownership of a 240, I find there are quite a few "new fangled" things on this car that I am not familiar with at all!
Thanks in advance.

 

I had this EXACT issue on a 1992 960 that we had for resale. I checked everything and I mean EVERYTHING. Swapped coils, plugs, injectors.

It turned out to be a failure of the intake manifold gasket. At low speed it would suck air in ahead of the injector and misfire. As the air velocity increased, it would run fine.

 

Great answer and one that hadn't occurred to me at all. I'll investigate in the morning.
Thank you - much appreciated.

 

I would also do a pressure test, the manifold gaskets are known for leaking on the 960s over time and allowing valves to get burned. i just found this out myself in october. I had a bad misfire in cyl 4 and couldnt figure it out. did a pressure test and found out my cyl 4 had none. hope u caught urs early. i rebuilt my engine after that.