Misfire P0300, 0302, 0304

Hi everyone! I've got some weird misfire which comes sometimes when I'm in traffic on idle (for hour or two).
Check engine light is blinking and I got codes above.

What I already done :

• new 8 Denso spark plugs
• new 8 Denso ignition coils
• cleaned throttle body
• cleaned MAF sensor
• New PCV Valve
• visually inspected all the connectors, wires and vacuum lines)
• compression is even on all cylinders (90-100 on cold and 160-170 on normal temperature)

I'm stuck, what should I do next? O2 sensor on Bank 2?
It's hard to troubleshoot it because problem is not always and it goes away when restart the engin

 

Welcome to the forum! Sorry that your first post is in regards to an issue you’re having. Did you clear codes after you replaced all the parts you mentioned? They might be lingering and in need of a code clearing with a bidirectional scan tool. As silly as it may sound, I’ve heard of more than one person disconnecting the battery and letting the truck sit for 20 or so minutes to also serve as a hard reset. It’s a free option that might help, so it can’t hurt. Best of luck!

 

My mind goes to fuel on this one, could be an old fuel pump/clogged fuel filter (its in the pump), clogged injectors. Might want to run a can of sea foam or similar through the gas tank then think about a fuel pump/filter replacement. Multiple cylinder misfires is odd, same bank though.

As stated by Brey doing a relearn is a good idea as well as using an OBD2 bluetooth scanner while driving to see your fuel trims/etc. to isolate a cause.

 

Thanks for response!
I did clear all the codes.

Maybe I'll try to swap injectors to eliminate this possibility.

 

I would put the old ones back where you have the misfires. It's an easier troubleshoot, before you involve the injectors. If you purchased these from ebay or Amazon, I would be iffy about both coils and sparks..

 

Bought it from RockAuto.
I replaced them because thought that was a reason of misfire

 

Must've missed that portion. Any chance it's ingesting fluid maybe from the valley?? I would still swap old coils in just to ensure your new coils aren't faulty out of the box. Check your battery ground wire