Misfire at 2800 RPMs

on cylinder 3&6 i have swaped coils with other one but still same problem plugs are new and swiched wiresalso with no change any help would be apprecated

 

sounds like it has to do with timing, do you have a timing gun because sometimes when the timing is off it will idle but once you increase the RPMs it gets worse and could be the cause of the misfire

 

thankyou for your respomse no dont have timing gun but will get one if that is a possible fix but i think it might be something diff cause runns smoth till get ti bout 2800 rpms and then stumbles alil code reader p0300 p0303 p0306 but only when i go 60 mph or in 2nd about 2800 rpms

 

Possibly a air flow problem intake or exhaust. Could also check fuel filter and injectors.

 

yea i didnt realize it was a 99 when i responded (guess i should pay attention to the year) not sure if a timing gun will work as i dont think the 99 has a distributor for timing, pretty sure its electronic timing.

 

What kind of parts did ya use, Toyota's like denso parts, the AutoZone crap not so much , and did you replace coil(s) or just switch cylinders , your post stated "other one" so not sure if that means swapped cylinders to see if miss followed coil or if it or they are new.

 

THANKS AGAIN I HAVE DENSO PLUGS sorry for caps and all a did was swich coils on cylinders but still reads 3 and 6 cylinder missfire
runs real smooth til i hit 70 mph in drive or stomp on it for passing then it stumbles and check eng lite flashes or if im in 2nd and accelerate it will stumble at low speed was wondering if throtle sensor could be faulty

 

Put new coils and wires on it ,should fix it , boss just did same thing on his 01 4runner for similar issue

 

so after many attempts at curing my check engine lght changing my fuel filter did the trick hope this helps someone
the lack of fuel caused the miss fire butit still has stumbling at high rpms

 

Have you checked the gaps on your plugs? Somewhere between .041-.043.

 

Think it was sabatoge? Or did you soak the engine bay down when you washed it??