Bad misfire

williala · Post by **williala** » 22 Nov 2013, 15:31

2008 90 3.2

I decided to check the condition of my spark plugs today, (96,000 miles) and took out #5 and #6 plugs and they looked great. Very clean.

I put them back in, made sure the coil packs were well seated and upon startup, a very bad misfire occurs.

Took it to Autozone for a OBDII scan and came back with thee codes:

P0300
P0301
P0302
P0303
P0304
P0305
P0306
P050b

Any idea what would cause a misfire code on all cylinders?

williala · Post by **williala** » 22 Nov 2013, 16:11

An update:

I disconnected the wiring to the coil packs to #5 and #6 cylinders, and there is no difference in how the engine runs. So obviously, both cylinders are not firing.

Post by **boosted5cyl** » 24 Nov 2013, 21:35

If those plugs have been in there from day one, its time to change them, regardless of how clean they appear. Did you check the gap or inspect the electrodes?

Did you disconnect any vacuum or intake related piping when you checked the plugs? Multi cylinder misfire -may be caused by this. Also, is it possible to accidentally swap the wiring on the plugs 5&6 on the 3.2?

I would start with a fresh set of plugs, clear codes and see how the motor runs. If the misfire persists you could swap coils 5&6 with 1&2 and see if the misfire moves.