P0300, P0304, P0307

My 2008 tundra 5.7 has these 3 codes. I've replaced all of the ignition coils and spark plugs. I also replaced the 4th fuel injector valve. I also cleaned the maf sensor and throttle body. What can be the problem? Please let me know. Thank you!

 

Join this but have a feeling there won't be many comments... Personally I have P0300, P0303, P0305 (looks like Bank 1 only). New spark plugs, swapped coils but the issue didn't follow. Currently in a shop for diagnostic.

 

Valves need adjustment? Noticed any coolant loss?

 

Not sure... Coolant was changed recently (the truck also was purchased a month ago); no losses so far.

 

Need to do live-scanning. Various tools available but one is Torque Pro. https://play.google.com/store/apps/details?id=com.pjt.realtimecharts_v1&hl=en_US

Assuming you have a fresh air cleaner, good PVC (rattles if shaken) and you've removed the negative from battery for 30 mins to allow a full ECU reset?

 

Does it happen only when hot or always?

 

I couldn’t recognize those misfires. Dealer couldn’t catch it either while diagnosis. But the codes are there.

 

Going to check/do that. Thanks for the app advise. I have a wireless OBD reader.

 

I was working on another Tundra with the same code but will only misfire when hot. Turns out there was a small crack in the head and the coolant would put out the spark from the spark plug. The crack is so small it only expanded and leak when the engine was hot.

Had another car where the valves were loose just enough to trigger the codes but never misfired.

Hope the dealer is able to figure yours out soon.