Misfiring

[beetlebugman]

Hi,

New to the site.. I just acquired a 1998 Pontiac Grand Prix and a motor out of a 2005 Buick (both 3800's).. Got them switched out and now have a little skip... i'm using a test light to check to see which plugs are not firing as they should.. using the pointed end to stick stright into the plugs at the coil packs i found that #2 and #4 are not firing as they should. Questions

1: Can the Coil plate be tested
2: Can the Coil packs be tested
3: Any other suggestions as to why i would have a skip keeping in mind that cylinder #2 and #4 are on different coil packs?

[BillBoost37]

Swap the coils to different locations (I guess one at a time into teh 3/6 position) and see if the misfire follows to that cylinder. If so..bad coil.

[Tony Mendez]

I would avoid poking into the rubber boots to test your ignition system. Doing so creates a path for current to arc to ground via moisture. If you have been probing your plug wire boots in this manner you have potentially created a multiple cylinder misfire condition.