Hi,

I am new here and also a new Volvo owner. I have purchased a used 1996 960 as a project for my grandsons first car. The car has just rolled over 200k, it was running rough with a steady miss when we started. It had been sitting for over a year so I guess bad gas was part of the problem. Fresh gas and seafoam were added to the gas tank, still missing steady on one cylinder. Check engine light is on. Pulled the coil cover off of the center of the engine to expose the the coil packs. Started the engine, disconnected #1 coil pack, no effect on engine. Swapped it with #2. miss moved to # 2. Coil pack was cracked, ordered a replacemnt, installed in #1 position, Note miss was still in engine but not as bad. With the retaining bolt removed, lifted coil #1off of plug with engine running, good arc noted. Switched #1 coil to #2 position, repeated procedure, no spark arc noted, Connected #3 coil wires to #2, Good arc noted. So I am stumped. What would cause #2 not to fire. Do I need to reset the ECM or can someone tell what else to check. Plugs are good, wet and dry compression are good.
Any help would be appreciated.

 

its possible the wire harness connectors to the coils have cracked and that may need to be replaced. You can also see if somebody swapped connectors as well - see link below for reference

https://www.davebarton.com/pdf/960HarnessRepair960.pdf

 

Thanks for the info. Do you know how to test the ignition module output at the coil ?

 

https://www.hella.com/techworld/us/T...on-coil-2886/#

Scroll down to the diagnostics section. Unless you have an oscilliscope, you'll be measuring source voltage, input/output coil resistances and inspecting connections.

 

Thanks for the info. Dose it make sense that all of the other coils show a fluctuation in the teast light but the one, #2, stays on steady, no blink. I am reading the power cycle to the coil from the icm I think. No2 has no fluctuation in the power. From what I can gather, there are 2 icms somewhere under the hood. One for odd and one for even cyls. Can an icm fail on one cyl or do they just totally fail?

 

some reading on the ICM for you. If only one cylinder misfires and you try swapping parts, then I'd suspect a wiring/connector problem specific to that cylinder.

https://www.matthewsvolvosite.com/fo...ic.php?t=82931