I allowed my son to talk me into E3 spark plugs for the first tune up of our new used TJ. They worked ok for a week, but in week two I got a misfire on #3 code (0303 I think it was). I changed to champion 7034. Reset the computer by grounding + wire (disconnected from battery). The Jeep runs ok now but my mileage seems to have taken a dump. Looks like I've gone from about 15 mpg to about 10 mpg. I'm hoping the computer figures this out but I guess I should have stayed away from the E3plugs in the first place. We'll see how it goes.
An interesting side note: people always say plugs come pre-gapped. I think that's true but for the Champion 7034,it was the wrong gap. I had to regap each and every one. They came pregapped at 0.045 when the spec is 0.035.
I put E3s in my "05" TJ the same time I lifted it and installed 33" tires on it. I went from 18MPG to 15 but I think it is because of the bigger tires and needing a gear change. So far and it has been 6 months, I show no engine codes for anything. You may want to put it on a scope and have a diagnostic done. I think it's too important just to play around with.
I almost made the same mistake last summer when changing out my spark plugs. I did a search and found a ton of backlash against E3 plugs. Jerry B has really good insight into why the plugs are no good for our application.
I've been running E3 for six years and have over 60K on the same set initially installed. No problems. I have a rebuild, basically stock, different cam, same lift just different duration power band now comes in around 1500 and pulls all the way to rev limit, unlike the stock. Banks headers and cold air. I did onpen the throttle body up some; mostly removed the tapper. If I stay at 70 or less, I get 18-19 mpg. Above 70 - 85 drops to 16 and same with ac on. (FL summers suck) oh, I did replace stock fuel injectors with 23lbs Bosch and added a Gforce chip to simulate more air to get the fuel to run the injectors. Otherwise the ECM limits fuel to the injectors regardless.
An issue I am having are my banks headers keep cracking at the collector welds. I am on my 4th set, these are the "revolver" style and they sound much better...I just hope they don't crack. The cracking issues I found is due to the highway driving engine speed engine CHT temps (purposely runs extraordinarly lean for emmissions. Thus, the injectors and gforce. These last set of header did not show typical hightemp discoloration, so I am thinking I have checked that box. The headers are cracking at the weld line. Known as the weakest link in a weld...this still should not happen like it is.
But, the E3's are great in my opinion...I even run them in my 93 Harley Wide Glide.
E3 plugs are a poor quality high-hype plug that is best left for those who like snake oil. E3's claims are only valid when compared to a plug that is completely worn out... something they don't mention.
__________________ Remember that having a different opinion doesn't also require one to be a jerk when expressing it.
Update on the E3s I had in my TJ. I pulled them. Long term us didn't help my mileage. I got a set of plugs from my local Jeep dealer 6 months ago and they run the best so far. No, missing or loss of power. My mileage is still poor from the high gears and big tires. But my overall power band feels better. I have moved to Nevada and I am doing a lot of back country crawling. So far my TJ is doing great on the Mopar plugs. The price was reasonable too.