2001 sienna xle.after using both a\c units on a hot day,developed a po300 misfire cyl.2,4,6. not plugs or coils.any clue where to look next?

SOURCE: vw beetle 2001 misfire cyl 2

hi am no genius but is your car fuel injected ,if so maybe the injector maybe partly blocked and can cause the miss firing of the cylinder. maybe try some good carby cleaner ,it may help

SOURCE: 1998 Cavalier No Spark in cylinders 1 & 4

ignition mod. grounds,pcm or timing belt could all be it but, I would have to look at timing first.

SOURCE: 04 Sedona 3.5 cyl #2 misfire replaced coil,back again 5 mos later

How many miles on the plugs and wires? Misfire can be caused by either plugs or wires, after that check the injector for that cylinder. Let me know what u find. Curt

SOURCE: i have a 318i 1998, the engine light came on. i

Sounds like it may be running a bit lean - do basic checks for air leaks in the induction system (such as leaking manifold gasket, loose hose fittings to air flow sensor etc).
Condition of HT leads also worth a check.

SOURCE: 2001 Firebird 3.8 misfires

Check your alternator see if you have a drop in voltage on your tack,then it is the problem.I too was a victim of high price tune up and still had a problem with a misfire.and cover your coil pack with a piece of rubber water run of onto your power pack .Another thing is to use a silicone spray on all wires.