bad coil pack..?

[buddha]

So my car started to run like crap. I check all the coilpacks first unplugging one by one, turns out cyl #1.was not firing. But heres the weird thing, i swap coilpack coil #1 with coilpack #2, and #1 still dosent work. so i change the plug. still nothing. I check the wires in the harness, nothing seems to be wrong. I test for power coming to coilpack #2, and the two wires on the side dont show power, and the center one does, so i then check #1 and it has the same, power to the middle, and nothing to either side. i cant figure it out.

is there a different way to test the coil? has anyone ran into this problem before?

[capowered240]

I'm having just about the same problem with mine but mine is with #3. I test all coilpacks, there good. pull spark plugs to check for spark and they are all getting spark, but when pull the connector off #3 coilpack with the engine running, it doesn't change. I'm getting really frustrated with it because I can't figure it out.

[biosehnsucht]

The FSM describes a specific method to test the coil.

Testing for power to the coil doesn't really work, since you'd have to be doing this while it's firing at high voltages and then try to get momentary readings that are very short in duration.

If moving the coil pack doesn't move the problem, then it's either injectors, wiring, or ignitor.

How did the #1 plug / cylinder look when you removed it? Might want to reference that to see whether it was not sparking but had fuel, or possibly sparking with no fuel.

[capowered240]

Mine is getting spark when I pull it out to check for spark, but when I put it back in it's not. When I look it the cylinder after pulling #3 spark plug, theres like a puddle of gas on top of the piston I guess because I'm not getting spark.

Buddha, let me know if you figure it out.

[biosehnsucht]

er, I wasn't paying attention, for some reason I thought you said #1 not #3..

but yeah, pooling gas implies spark is failing for some reason.. thats odd that you can spark it in free air but not in the cyl.

check the FSM there is a procedure to test it, you check the resistance between two pins.. forget which two and what value you're looking for but more than a certain variance from spec and its toast. I've had a few bad packs that would work off and on, when they got hot they'd start breaking up..

[capowered240]

When I moved #3 coilpack to #4 and #4 to #3 and pulled #3 it still didn't make a difference. I'll test them again, but when I tested them they all tested good.

[ccasey645]

sounds like the ignitor to me

[capowered240]

I have one other ignitor that I had got along time ago, I changed it out and still the same thing.

Well there was one thing that wasn't right. I had changed out the spark plugs out along time ago. Well I bought some new ones and when I was pulling the spark plug #3 out, the white part of the spark plug that the coil goes over, it was broke in half to where I could see the middle of the spark plug. I don't know if that has to do something with it or not. The others were fine.

[ccasey645]

Yes that would deffinately be your problem. The spark was grounding out on the block before it reached the gap, had that exact problem on a blazer I worked on lately. It had been missing at low rpms and the porclen on one plug was split so the spark never got to the cylinder, just arc'd to the block where the insulation should have been.

[capowered240]

Ok, but I had just put new spark plugs in a couple of days ago. It still not getting fire.

[ccasey645]

Oh, my bad. Wierd. Well I didn't see it mentioned before, but have you tested your injectors? Maybe that cylinder is getting spark, but no fuel?

[capowered240]

Its getting fuel but no spark. When I pull the plug out of 3, there's a puddle of gas on top of the piston. So I know the injector is working.

[buddha]

i am getting fuel, and i swapped out plugs and it did the same, i also swapped chips, same thing.

[capowered240]

Have you checked to see if you are getting spark when you pull the spark plug out to test it? I'm getting spark when I have the plug out, but when it is in I'm not.

[buddha]

i unplugged the ecu then plugged it back in now it works fine

[capowered240]

I've done that to but it still no difference.

[capowered240]

I had tested the coilpacks today and they ohm out at 1.0 ohms. That is three of them. The fourth one was 0.0 ohms. I saw that you had said that the test doesn't really work. It's in the fsm though. In the fsm it says they should be between 0.6 - 0.8 ohms. I guess I'll be needing some coilpacks. All four of them.
Modified by capowered240 at 10:45 PM 9/25/2006