I been trying to figure out why my car keeps misfiring I changed one of my valve covers (because there was oil in the spark plugs) so I changed that the spark plugs and the coil packs then I changed the spark plugs on the passenger side they was black so I thought that I fixed the problem but when I turn on the car and drive it the engine light starts flashing then the engine code still says P0300 I’m so frustrated what should I do??

 

Did you get the coil pack harnesses mixed up?

Check out this post for the coil pack wire colors.

https://g35driver.com/forums/g35-sed...ml#post7207226

Also, what about the spark plugs on the left side, did you change ALL of the spark plugs?

If both those things check out I would start looking for a vacuum leak, check the fuel pump strainer baggy, fix the P0024. Is this a rev-up DE or an HR engine?

 

I changed all the spark plugs on both side I just checked the harnesses and the all look connected to the right coil packs I just did a compression test today and the engine is fine but everytime I drive it to 30-40 mph that’s when it starts miss firing and the battery light and the brake light keeps flashing and turning off when it’s in park sorry I don’t know too much about cars so I don’t know is it’s a DE or HR

 

Pop the hood, do you have one air filter/tube/throttle body or do you have two (one on each side).

One intake is the DE, two intakes is the HR. The DE came in two variants, the normal that just has intake cam actuation and the rev-up version which had both intake and exhaust. You can tell them apart by the cam timing cover, the rev-up has a sort of "waffle print" on it, I'm guessing you probably don't have the regular DE because I don't think it can throw a P0024 code because it doesn't have the exhaust cam retarders.

Sounds more like you have an alternator problem, loose battery cable, etc. Battery light usually means electrical issue.

 

Have you resolved it?

 

I smell bots...