Coil, But Which One

[Husker Z]

Okay, if you remember a while back, I changed my valve cover gaskets and found a ton of oil in the spark plug holes. I cleaned them all up and cleaned the coil springs and everything else. Put it all back together and everything was great and ran great. Well, a couple days ago I noticed a slight hesitation at low RPMs, mainly in overdrive on the highway, but sometimes you'll feel it miss while sitting at a light. Funnything is, you can accelerate from a stop and not miss a beat, feels great, or you can sit in the garage and slowly go through the RPM's and never feel anything. Anyway, I'm assuming one of the coils is bad, but my question is, how do I tell which one it is? I'm really not in a position to throw $600 at a set of coils if I don't absolutely have to. Any suggestions would be great.

Thanks in advance.

 

[mrzeee]

A complete set of 8 coils would be $350.00 and for a 6 cyl it would be $270.
Short of taking it to a shop with a scope, Maybe you can pull a plug to see which is fouling??

 

[Husker Z]

A complete set of 8 coils would be $350.00 and for a 6 cyl it would be $270.
Short of taking it to a shop with a scope, Maybe you can pull a plug to see which is fouling??

I guess the only other option is to hope it throws a code and then read it with a scanner?

 

[rickztahone]

that's what i would wait for. once it throws the code it's easy going from there

 

[Husker Z]

that's what i would wait for. once it throws the code it's easy going from there

Yeah, I'll probably do that. It's not bad right now, not like it was before I changed the VCG. That time, the light came on (blinking) and within 10 minutes, it was barely driveable. This is pretty intermittant.

 

[daves2000ls]

Check the boots to see if any are damaged. If they are damaged/mis-shapen you can pretty safely bet they need to be replaced. Be thankful you've got the V8, otherwise all that work you just did would have to be undone to get to the passenger side bank. Good luck at finding out which coil(s) might be failing.

This might sound odd, but I think it might help you out. Simulate driving in the rain, hard rain. I had an intermittent miss and one day it was raining and my CEL came on long enough for me to get to Advance and have them read the code, mis in cyl. 4. Front of the engine on driver's side for the 6. Just an idea.

 

[eastcoastLS]

+ if you wait til it throws a code, hopefully by then you will have financed for all new coils.

 

[rickztahone]

go with GMS coils

 

[Husker Z]

Check the boots to see if any are damaged. If they are damaged/mis-shapen you can pretty safely bet they need to be replaced. Be thankful you've got the V8, otherwise all that work you just did would have to be undone to get to the passenger side bank. Good luck at finding out which coil(s) might be failing.

This might sound odd, but I think it might help you out. Simulate driving in the rain, hard rain. I had an intermittent miss and one day it was raining and my CEL came on long enough for me to get to Advance and have them read the code, mis in cyl. 4. Front of the engine on driver's side for the 6. Just an idea.

That may be a good thought. When I was replacing the VCG, I didn't notice that they were mis-shapen or anything, but it didn't seem like they grabbed the plug like they should.