If you are misfiring in a cylinder how do you know if it's the spark plug or the ignition coil?

 

switch the ignition coil.

 

Switch ignition coil, and if you still get a misfire on that cylinder take the spark plug out and look if the ground electrode isn't bent.

Once I changed spark plugs and got a misfire. So I took the spark plug out and the ground electrode was bent all the way in so there was no gap at all.
I regap it and it's fine since then.

 

to check the coils, you want to ohm them out to make sure they are still good. check out the spark plug, when i had a miss fire it was cause by my fuel injector

 

ur missing one huge possibility.


injector.

 

sorry to barge in on the thread but i also had a cylinder misfire on the max i just recently purchased...the guy said he had a tune up recently done where they changed the spark plugs. So im putting 2 and 2 together and was wondering if in fact they put bosch plugs in the car instead of NGK would that cause a misfire? If so is there a way to tell my looking at the plugs if they r bosch or not? Also it is true that bosch plugs r horrible for our maximas right?

 

bosch = bad. the only way to tell is to take them out and look at the names on the plugs.