[Peter P.]

Dear all, my 2010 Sienna, 330K mileages, begins to misfire only when hot, when I drive it for 10 miles. And when it happens, I pull out, shut off engine and restart engine, the misfire can be gone and work for a long time, or a short time. The error code are always P0300, P0302, P0304 and P0306. I replaced all spark plugs, all plug coils, the injectors for cylinder #2,4,6. But the misfire always comes back when I drive it for a while. But of course, it can be get rid of by restarting engine.

I don't know what parts are the next to be replaced. I appreciate any suggestions from you.

Thanks,
Peter

 

[fibber2]

Welcome!

Do you have the ability to examine the "Freeze Frame" data stored along with the DTC's? Things to look at would be the number of misfires per cylinder (all the same, or predominantly one bad cylinder, etc.), any VVTi cam phase involvement (as all your bad cylinders are in one bank, that's probably your cause), any short/long term fuel trim issues on that bank (you could have an intake air leak), etc.

A bad OVC (external) or cam gear spool on that bank is likely your problem. Sometimes you will also see a P0015 thru P0022 code along with the misfires indicating a cam that isn't tracking properly. Simple code readers can get overwhelmed with all the data being delivered.

Throwing expensive parts at the vehicle without knowing what's wrong is, well, wrong.

 

[Peter P.]

Welcome!

Do you have the ability to examine the "Freeze Frame" data stored along with the DTC's? Things to look at would be the number of misfires per cylinder (all the same, or predominantly one bad cylinder, etc.), any VVTi cam phase involvement (as all your bad cylinders are in one bank, that's probably your cause), any short/long term fuel trim issues on that bank (you could have an intake air leak), etc.

A bad OVC (external) or cam gear spool on that bank is likely your problem. Sometimes you will also see a P0015 thru P0022 code along with the misfires indicating a cam that isn't tracking properly. Simple code readers can get overwhelmed with all the data being delivered.

Throwing expensive parts at the vehicle without knowing what's wrong is, well, wrong.

Thanks a lot! I appreciate your help. I will check the Freeze Frame today and will post here. Thanks again. Peter