2004 V6 Random Misfire

[chris.817]

Hey folks. My 4runner has been sitting for several weeks for some projects and finally back on the road this weekend. Drove it twice for 15-20 miles with no issue. Today, i head out and at first stop light it dies. Starts right up but won't idle without my foot on the gas a bit but otherwise seems fine. After several miles it seems to have cleared up (idles around 5-600 rpm). I get on the highway and it starts to run rough. Engine light comes on.

Codes present are P0300 and P0302. Cleared codes and drove home. Same rough running. Read codes again and just the 300 this time.

Only things I've done in last 24 hours is a tank of gas (87 octane which I usually don't do but I'm questioning that) and I tried in vain several times last night to do the zero point calibration to include disconnecting my battery for several minutes.

Anyone ever have this happen so suddenly and severally?

Thanks.

 

[AuSeeker]

A member here had a similar issue recently, the links are for his topic on his issue and then his other topic on fixing the issue.

Really, really weird misfire problem

Update on Weird misfire problem

 

[Burt]

Due for set of plugs?

 

[chris.817]

Misfire resolved

Thanks folks.

Sad that it takes an OBDII scanner and the power of the Internet to tell me I need to change my spark plugs... I've only owned this vehicle for about 3k miles. Maintenance history shows they have about 90k miles on them. Picture is #2 plug. #4 similar. The rest not near as bad.

As you can see, the dealer did not sell me Iridium plugs...

Misfire gone. Idle is still low at about 500 rpm.

 

[importman]

Thanks folks.

Sad that it takes an OBDII scanner and the power of the Internet to tell me I need to change my spark plugs... I've only owned this vehicle for about 3k miles. Maintenance history shows they have about 90k miles on them. Picture is #2 plug. #4 similar. The rest not near as bad.

As you can see, the dealer did not sell me Iridium plugs...

Misfire gone. Idle is still low at about 500 rpm.

I'm the one who had the weird misfire that someone linked above. Funny but my #2 spark plug was bad and that's all it took to fix it. But mine had codes for 1 and 2 which is what made it so weird. Anyway, I wouldn't fret about the non iridium plugs. Toyota calls for standard plugs on our vehicles. My understanding is the only benefit to iridium or platinum is longevity. So they stick them in any vehicle that requires extensive labor to replace them. And as you've probably figured out by now the plugs in ours are fairly simple to replace. Glad you got yours fixed. Oh, and about that low idle. If you've had the battery unhooked the idle will be low for a little while until it relearns where it needs to be. If you haven't had it unhooked I'd suggest cleaning the throttle chamber and plate. That will pick it right back up to where it should be. Good luck.

 

[sailgreatlakes]

I like seeing these mystery problem threads pop up, even if the solution ends up being something simple, it's a good reminder to consider some of the more obvious problems! I may have to inspect my spark plugs now, just to be sure haha