i have always been running NGK BPR8ES and this exact same problem started happening to me today
could it be the cold weather or something?

 

Something similar happened to me, it started cutting at around 13psi so I regapped the plugs and it fixed it untill I got to 18psi and it started boost or load cutting. A simple data log to check for knock and changing the load/boost threshold will fix it if you hit this limit. Has your car been retuned?

 

thanks for the help guys im goin to try a set of new ngk's first today

thanks for the idea but im catless

 

I'm glad you said that, I run BR7EIX in mine, I have some basic mods and a tune on an '03 Evo 8, it runs perfect.

 

For cars that are mildly modded and have a tune the BR7EIX (iridium) will last longer than the copper BR7ES or BPR7ES other than the material, the difference between the BR and the BPR is the "P" stands for protruding plug. The non protruding plug will draw heat away from the plug as it transfer it to the head and dissipates it better as I stated earlier. If you are running untuned or have a huge turbo and change your plugs all the time then it is not worth it to buy the more expensive Iridium plugs and the coppers will work just fine for 3-5k miles or so.

Josh

 

I just noticed you're in NC, where ? I'm near Hickory and need a decent place that knows Evos. They are kinda hard to find in my area.

 

Fayetteville, it's worth making the trip to them

 

Do they have an AWD Dyno ?

 

I just picked up a set of ngk's but they gave me bpr7es-11 is that any different because of the 11 or am I ok?

 

hey guys just an update put a new set of bpr7es in (only ones instock) and the car runs 100% again

thanks to everybody for the help/ideas

 

I second that. Same thing happened to me.

 

i was having the same problem. i install the ngk bp8es plugs and gapped them down to .024 and my car runs like a champ now. i noticed everytime i would go wot in 3rd the car would sputter for a sec and then haul azz. now it doesnt do it anymore. i know they are cheap plugs but im going to change them out every oil change

 

i will not play with anything else but NGK`s in my evo

 

Chris Black @ AMS changed mine over to NGK Copper BPR8ES gapped at .020. I am actually running autolites right now because thats what I could get my hand on in a hurry. No problems with them, but I do plan to go back to NGK. Your gap is way to big.