Anyone know what the resistance of the coil packs should read on a 2007 Hummer H3. All of them read around 9.5k on the primary and around 45k on the secondary side but one. The one reads 9.5k on the primary and 6.4k on the secondary. I figured that one must be bad so I bought a replacement but the replacement reads 9.5k and 6.4k so either the new one is bad or I actually have 4 bad ones. What led me to hear in the first place was a misfire in the engine. The computer said it was number 4 and number 4 was the oddball or so I thought. Turns out I had the numbering wrong and #4 was reading 45k and the one I thought was #4 was reading 6.4k. I can't find anything anywhere online about this. I can't even find it in the GM service manual.

 

It is one of those don't need to know that things.

Coil on plug packs are cheap and easy to test.

First thing to do is check the wiring to all the coil on plug packs paying particularly close attention to the suspected bad one. The misfire code tells you which is having an issue.
If all looks good, jut take coil pack #4 and swap it for say #1. If the miss follows where you put it (the miss or P0304 code is now a P0301) you just confirmed the coil on plug pack that started at #4 & you moved to #1 is bad.
If the miss stays at #4, then you have a wiring issue to CP #4, or a spark plug issue.

 

Don't need to know? If I knew I'd have the answer I was looking for in 5 seconds and not have to wait days. Most manufactures tell you the specs but not GM or AC Delco.

 

Don't need to know meaning you're digging way to deep, easiest test is what Doc said.

 

How is climbing into the engine to remove the air intake, swapping around the coils, putting it all back together, waiting to see if the engine light comes back on and then driving 20 miles to an auto parts store to get the code easier than a 5 seconds resistance check?

 

If your auto parts store is 20 miles away, may want to invest in a scanner for yourself.. Either way you do whatever works for you.

 

Did you correct the issue?