What Exactly are the signs of an engine “miss”??

[dreamer2355]

It will depend on the type of misfire. If its a class A misfire on a OBD2 system (flashing CEL), you will notice a rough idle as well as rough running conditions.

Other misfires you will experience under a load.

One of the better ways of finding a misfire with no scan tool data is to do a power balance test as shown in Eric’s video below –

http://www.youtube.com/watch?v=bAOmUjAjNjE&feature=plcp

Misfires can also because for many different reasons from fuel delivery problems, ignition issues, vacuum leaks or even compression issues.

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[JDM_Hatch99]

The video demonstrates this test with a car that has coil packs. Since my car has spark plugs do i just pull the spark plug wires one at a time?

[dreamer2355]

Its probably safer to pull fuel injector connectors rather than pulling ignition wires.

I would use a rubber glove if you decide to use that method of puling ignition wires while the vehicle is running and have someone standing by incase you get zapped. Its hurts, ALOT.

[EricTheCarGuy]

“Miss” is short for “misfire” so you already have the definition. It can be caused by many things and it may not be consistent depending on the cause.

[Author]

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