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Discussion Starter · #1 ·
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?
 

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Registered
84 Coupe w/500
Joined
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5,671 Posts
Probably still gonna be related to the spark. Opti, wires or plugs. Take it back to where you got it done if you have a warranty.
 

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Registered
1994 Fleetwood 60" Stretch; '07 Avalanche, '95 Nighthawk
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3,963 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.
 

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Super Moderator
2014 ELR
Joined
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10,391 Posts
For quick, cheap, and easy, put a new coil wire on it. While doing that inspect/clean/lube all coil electrical connections.
 
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Discussion Starter · #5 ·
Thanks guys, How does one "put a new coil wire in it?"


Im gonna take it to my friends house so he can look at it in his garage. What exactly should I tell him to look out for?

Thanks again guys...
 

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Super Moderator
2014 ELR
Joined
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10,391 Posts
Coil is on the end of the driver's cylinder head. The wire goes from that terminal above the "C" to the opti.

 

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Registered
68 DVC, 96 FLTWD Brgm, 11 CTS Premium (two)
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1,695 Posts
RThere is a coil wire, it's the 9th wire on the Opti.

You mentioned changing plugs and opti but not wires, i recommend changing the wires as well, they do go bad.
 
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