P0301 and P0300 misfire codes

[Tj_krawler]

Can’t figure out my codes. I’ve replaced spark plugs, replaced coil pack with oem pack from the dealer. I’ve tried sea foam, cleaned my injectors and replaced the o-rings. Replaced the camshaft position sensor. Was thinking it could possibly be the head gasket? Someone plz help

 

[Chris]

Have you thoroughly inspected the wiring harness for breaks in the wiring?

 

[Tj_krawler]

Have you thoroughly inspected the wiring harness for breaks in the wiring?

So far there are no signs of the wiring cracking and any signs of splits

 

[Chris]

So far there are no signs of the wiring cracking and any signs of splits

Sometimes they can be hard to find. I would also probably do a leak down test. It’s always possible you could have a cracked cylinder head or something.

 

[Tj_krawler]

Sometimes they can be hard to find. I would also probably do a leak down test. It’s always possible you could have a cracked cylinder head or something.

I will have to try that this weekend hopefully it’s nothing tooo serious I miss driving my Jeep

 

[CharlesHS]

What spark plugs are you using ?
Some Jeeps have adverse reactions (don't run well) with the recommended platinum spark plugs due to the waste spark system; I speak from experience when I say this...
Initially I installed the recommended platinum tipped plugs and with in a short period of time I ended up with numerous misfire codes. I consulted a friend who worked at the Jeep dealership for 25+ years and he stated that factory recommended due to all the misfire problems; the NGK spark plugs should be used. When they are used there are rarely any misfires.
We installed the NGKs and did a combustion chamber cleaning; the misfires went from over 80-100 misfires in a 200 second window of time to 0-2 misfires.
Periodically I run Seafoam cleaner thru the fuel tank and the misfires have stayed gone.

 

[CodaMan]

Quit throwing parts at it and troubleshoot it.

https://wranglertjforum.com/threads...the-dreaded-misfire-and-how-i-solved-it.4212/