OK, OK I know the truck plug is the standard for 4.0 but I have read sooooo many thread posts about plugs where on person says the bosch +4 made their jeep run like crap and then there are others that say they run nothing but those in all their cars and have improved throttle response and better mpg. So my question is about the E3 plugs, what part number and what result in what year xj. PLEASE FOR THE LOVE OF JEBUS, THIS IS NOTTTTTTTT A THREAD TO BASH THE E3 PLUG. I dont care what your uncles brothers neighbors friend Terry told you they did to his wife/sisters pinto. I want first hand info about them. If they worked, great and if not then thats fine too. Also do not say "stick with X plug". If that was the ONLY plug that worked then that means that anyone seeing positive results from any other plug than the copper or truck plug is either A) lying or B) full of $h**. That cant be the case becuase I have friends running the +4 in different 4.0 jeeps and having positive results, while my 90 did not like them so much. First hand about the E3 and your results only please.

Thanks in advance!

 

Mine had autolites in it when I bought my cherokee. I put E3's in my 2000 and it started stalling out. I swapped them out for champion coppers and the problem went away. I didn't notice any change in performance or economy but I didn't have them in for long enough because I couldn't stand the stalling out. That's just my experience I hope this is what you were looking for.

 

i had E3's when i bought mine, the only thing i noticed was a faster startup, my champion copper's give me better mileage and more power (according to my butt-dyno)

Though it could be cause the E3's were old, fouled and it sat forever

 

I have ngk's in mine and dont notice any problems, cant remember what it had before. It has allways take a little long to start from cold though. I went from bosch +4's to the "latest and greatest" iridium platinums in my bmw and noticed a good power increase.

 

I have E3s in my 08 Subaru Legacy and love them! They have been in for 45k (car just turned 100k) and still work great.
I did notice a better throttle response and a slight (less than 1MPG) mileage increase. I will be buying these plugs again.
My XJ has Bosch platinum in it right now as they were new when I got it so I will be running those for a while.
I have bought Splitfires and and +4s and didn't like them. My old Subaru Impreza would burn a Platinum plug up in 10k but copper would last 50k. I wouldn't blame the plugs, they were just not right for the application.
I think that the people who say use this one plug in a given vehicle are a bit narrow minded and need to experiment.

 

I have the E3 plugs in my 97 Xj 4.0. In my opinion these are alot better than the champion plugs it came with. faster/better startup, better throttle response and a very small gain in mpg but i'll take whatever i can get. Smoother idle. I'd buy them again, put them in my 08 yukon and gained 3 more mpg... a friend put them in his 09 jeep compass, and gained 6 mpg, hard to believe but it happened.