Wait..isn't the whole reason we change spark plugs, IS because of the motor needing tuned up? I'm confused...I stated that after changing spark plugs I got an MPG gain, which would make the reason I changed them because I was getting less MPG's, would it not? I do agree, the E3 spark plug do not work for all makes/models/engines, but I have had success with them in both my 01 Grand Prix with 3800 Series II, and that 93 Jeep Cherokee with 4.0 I6(which if you talk to Jeep guys, Champion Copper is the only thing to use), but I also read about guys changing them out every 20,000 miles because of a decrease in mileage, or fouling problems. Yes, it's a great possibility that they had more issues in their motor than spark plugs. Fact is, I am going to research and read what others have put in their motors, see what the biggest complaints have been...already in this thread you have people loving Champion Copper, Bosch +4, and E3, might even see a few people pipe in liking NGK or Autolite, maybe even Denso...research is key, and you will NEVER know how they do in your motor unless you try them out...

 

Actually i been running bosch +4 for years no issues.
Also the MAP sensor do get a lot of carbon on them and a wire brush doesnt hurt them. everything I said before i have done, i do all my own work on my truck and the 318 is a solid work horse engine. Seafoam is only a last resort to clear build up from the cylinder heads and valves. Short of pulling the valve covers off to clean or replace parts.

as you can see from my pics of my truck its in top running condition and I get better MPG than it drove off the lot. But of course I have dropped 14k in to the truck and rebuilt 90% of it from the ground up.

Your correct on EGR I meant to say PCV they get gunked up as well

 

in 95% of these trucks bosch plugs will run like crap after only a couple thousand miles, with one exception, people who drive 90+% highway miles because that gets the engine good and hot, around town driving and short trips will foul up bosch plugs (all of them) as well as any multi-tip plugs (which in themselves are a scam to get more of your money)

also didnt you say you have 35s on your truck?? there is no way you are getting better mpgs with that tire setup than you got stock, there is no way in hell that im buying that.

btw i have a 4.7 and i get considerably better than advertised gas mileage out of it (16 around town rated for 13 and 19-20 on the highway rated for 17)

 

33's I average 18 in town 23 highway.

 

The copper Champion plugs that we preach every day is mainly for the 5.2/5.9 engines with the older style ignition system. They don't like Plats.

Plats are okay for the 4.7 as they have a different type of ignition system.

A good substitute for copper champion plugs are Iridium champion plugs. IR plugs blows plats away and the older style ignition system loves them. IR plugs are good for 100k miles and I believe that as I have roughly 50k on my IR plugs right now and they are still clean as ever. Super easy to start and my engine idles smoothly.

IR plugs are expensive. More expensive than Plats. If I recall, back in 2005 when I bought my IR plugs, they ran around $8-$10 each. But well worth the investment in the long run.

 

Do you have DOCUMENTED proof of that???? otherwise i can BS on that claim..

 

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