EGR is a possibilty. I am curious about the header issue causing it.

 

As am I. Seems i've seen more issues on multiple trucks posted as a result of the headers than anything else. I honestly don't know that the little bit of HP you gain from them, and that's if they are truely tuned in properly, is worth the hassle.

The big "BUT" here is, how could the headers cause misfires? I forgot to mention yesterday that, the mechanic put the heat gun on all the cyclinders, they were all running the same temp. there are no hot spots.

 

What about plugs? I am running a standard copper core TR55 in my truck. Could they be too cold to do the job?

Also, heard stories of MSD wires causing misfires for what ever reason. Thing is, my wires seem to be OK. We swapped an MSD for another aftermarket wire, and it did clear up cylinder one for a minute or two, but then the misfires came back slowly. Could it still be the wires? He showed me where it looked like the spark was breaking on the EFI live. You know how it shows the "pulse" screen. The plug he swapped it with was not a factory plug. Man, this is killing me. LOL

 

Not sure if you still have the original plugs if not try some OEM Delco Plugs and see if any thing changes. Maybe try some different wires.

I have seen alot of vehicles reject Spark plugs that are not of the same quality as the OEM plug. For Example the Honda uses and NGK or a Denso depending on year and application. In some cases we swapped brands and had issues. As soon as we put the original used plug's back in, it clears up. We order a replacement set of the same opposite brand and the same thing. Call the parts store and order the OEM Brand for that year and no issues. We can't explain it other then it must have something to do with the way the vehicle is programmed. Every thing is set up based around the OEM plug so if something is slightly different it may casue an issue. Every brand uses different Materials to construct the same basic part. I think today's computer controlled are highly sensitive to this.

I saw a Nissan Sentra that a customer replaced the Spark plugs with the E3 plugs and it stopped running a week later. He towed it in and we we were like WTF is wrong with this, it has spark and has fuel??? After some basic checks we pulled the plugs and found those stupid E3's in there. So we put some used plugs in there just to see if it would work and what do you know started right up. Swaped back and it wouldn't work. Customer couldn't believe it. So I did the swap in front of him and he was amazed. We ordered up new OEM spec spark plugs and sent him on his way. A few week later another customer wanted to do his own tune up and it started having the same problem. Towed it in and guess what??? Cheap plugs were causing his issue. I have seen this issue between Platinum and Iridium too if you mix them up.

 

Very interesting. I tell you what i'm going to do. I'm going to get some iridium plugs, factory spec, and drop them back in. What the hell, i've changed everything else. LOL!!!!!!!!!!!! Hey, maybe that's it. I always wondered about the TR55 plug, copper core, when the factory is suppose to be iridium. i'll make that change, and see what happens. Really appreciate the feed back. You close to SC? I'll have the wife watch the kids and I'll buy you a beer and we'll get swankled and eat deer tendorloin wrapped in bacon until we are retarded.

 

Ive seen alot of problems with those e3 plugs, and i run msd wires... No spark issues

Alot of guys will run those ngk coppers for boosted applications and whatever, but for just a dd i recommend delco iridiums...

 

Yeah, well, mine's not boosted. I think it might be the plugs. I'm picking a set of the high priced bastards this afternoon and will be installing them. I'll let you guys know what's up.

 

Ya just ask for the factory replacement delco's and remeber they switched from like platinum to iridum and the gap changed from .060 to .040 when they did so. Personally I liked the old plug better but it has since been discontinued. They seem to throw less fits.

 

Well that sucks. I swapped the plugs out, but left the factory gap of .060, as that is what the book called for and also what the plug came from the factory gapped at.

But, the way it is, the misfires are still there, in the same spot. But, it's running better. So, not all bad, just a waste of 60 dollars since it didn't fix the problem. What pisses me off is, the misfires virtually go away after the truck warms up and is on the road. I don't know what else to do. I guess i'll just drive it until it blows up. I don't guess random misfires here and there can hurt anything.

 

That fact that it goes away now when it warms up indicates you might be on the right track.

Try re-gaping the plugs at .040. The book says .060 because that was the old spec for the original plug. They went from Platinum to iridium and it required a tighter gap. Which should be .040.