Can someone tell me the order of the cylinders on my 07 hummer h3 L5 3.7L Someone told me it was 1-3-5-4-2, with 1 being in the front of the engine (near the radiator). I need a second option please because I need to change my misfire on number 2.

 

That's great you found #1, next in line is #2.
Btw, 13542 is the firing order, the cylinders don't move.

 

So sorry about that mis take. I'm trying to cut on cost and fix some of the issues on my own. I got a cylinder #2 misfire today. So I'm going to try and change the Number two coil and spark plugs.

 

Please help me. I have a cylinder misfire p0302 on my 07 hummer h3 and I want to fix it. I'm going to check the ignition coil and spark plug on cylinder 2 since that's what the code say. The problem I'm having is the cylinder order in the engine bay. I can see the ignition coils all 5 but I don't know which one is number 2? Is it 1,2 3 4 5 starting from the front of the car or is ignition coils #2 in a diff order. This is what I'm confused on.

 

Hummerz already helped you.

The cylinders are numbered front to back, starting with #1, like you said, and then #2, like Hummerz stated, on to #3, #4, & #5 in the rear.

The firing order, or the order in which each cylinder sees spark/combustion, is 1 - 3 - 5 - 4 - 2. These aren't the numbers of each cylinder, they are the firing order. So, cylinder #1 fires first, followed by cylinder #5 firing second. Does that make sense?


Check the coil on the 2nd cylinder from the front.

 

thank you makes sense.

 

Here's a map for you(GPS not needed):

 

lol thank you I got it im going to change cylinder 2 check the coil and spark plug.

 

So today, 2/6/23 I was checking codes on my H3 for a P0442 small Evap leak. Well I bump to another code for Misfire on cylinder 2. P0302.
I had the same questions as everyone about which one was cylinder 2. Found this thread and I try to understand about the alignment of cylinders as 12345, and firing as 13542.
I decide to start to remove the air box from top, to proceed to check all the wires of each coil connection, before removing coils and spark plugs. I notice 2 wires from cylinder #3 shaved from top due to the air-box rubbing from all this years. And before starting to investigate cylinder #2, I proceed to fix the wires. I figure there was a high chance for the electricity to be arching or jumping back and forth. After this I place everything back together not thinking that this small repair was the reason for the misfire.
WHICH this give me the reason to add this to this tread. The misfire was on cylinder #3 not on cylinder #2 as stated on the code. Meaning that the misfire is on the 2nd cylinder that fires after the 1st cylinder. So fire line is 13542. Cylinder #2 = 3rd cylinder.
Hope is not confusing.
On a misfire code, they refer to the cylinder on the order that are fire. NOT on the cylinder number line.

 

Nope, the cylinder number does NOT change. #2 is the second from the front. P0302 definition: Cylinder 2 misfire detected.

Has nothing to do with firing order. You made an anecdotal conclusion based upon your messing with the wiring one time. If your coil on plug pack for #2 is bad, you fixed nothing. The way to confirm this is to swap the coil on plug pack from #2 to say #5 and see if the misfire follows the swap to #5.