Cadillac Owners Forum banner

Need help finding causes for random multiple cylinder misfire on my 96 FWB.

3640 Views 6 Replies 4 Participants Last post by  cadillacmike68
The other day my check engine light came on again,second time in the last few weeks, and then went back off the next day.

It happened while my car was sounding like it was gonna turn off, and it was shaking... I got the codes ran and it was a po300, multiple cylinder misfire..

I got all of my spark plugs and my opticap replaced last year... It feels like my cars running on 7 cylinders or something, and feels maybe like one of the spark plugs is bad or unplugged because sometimes when im idling my car starts to sound like its gona die and starts to shake...... I do have an exhaust leak, but What do you think could be the cause of this?
1 - 1 of 7 Posts
Check the wires. My #7 wire was arcing against the block causing a misfire. I haven't replaced it yet - repositioning it seems to have fixed it for now. Watch the engine run in the dark - you may be able to see arcing if you have a bad wire.

They could've cracked a plug, too, when installing them. It's rare, but it happens.

I agree, thought, that it's most likely ignition related.
1 - 1 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.