I have recently had the clutch in the car done and after break in i went out and drove the car hard and no problems... Now all the sudden when i try to do a hard pull i get to about 3/4 throttle and the car misses or fuel cuts not sure really and studders bad and falls on its face. I changed the plugs tonight went out again and same thing i cant give it full throttle or it studders and falls on its face violently... Any input on what this may be?

 

has it ever been tuned? if not then its probably hitting fuel cut. the air is cooler/denser now so its easier for the turbo to make boost now then it was when it was warmer out.

 

What plugs are you running? I suggest NGK BPR7ES. I believe what you are experiencing is boost blow by.

 

Im not sure if it has ever been tuned i bought the car from a lot in alabama and had it shipped to me in ohio.. I put the autolite double platinums in it because noone around me had the right ngk plugs i looked everywhere... Not sure what boost blow by is and also what would be causing a fuel cut?

 

Is it sputtering when u cut? I had a similar issue when I first bought mine, turns out my plugs were bad

 

sounds like a fuel cut. as for the spark plugs you could always get it online or through a vendor on here. http://www.spoolinup.com/
also you definitely need to get it tuned. since u r in ohio bring it to buschur in wakeman.

 

its just a real weird cut. im gonna try to get the ngk plugs online and see if it helps. What would be causing my fuel cut though?

 

and also blue by u i called a parts store by me and they have the bpr7es in to styles the regular for 1.99 each or the bpr7es g power for 2.49 each not complaining about price at all but seems kinda cheap? or is that normaly what they run?

 

and which of the 2 do you guys recomend? g power or regular?

 

kmevo3,

The regular ngk's are fine. As long as the part # is bpr7es, youre good. Where in Cincinnati are you located? I live 10 minutes south of Newport. It sounds like youre hitting boost cut. I just reflashed an evo last week that was experiencing the same issue. As it gets colder, you tend to hit boost levels beyone the maps range and it will fall flat on its face. Id be happy to pull your ROM and look at it. Do you have a way to log boost?

 

setting in the rom that needs fixed. mitsubishi made the dsm's and evo's and pretty much every other boosted car they made equipt with a fuel cut function which is activated when the ecu reads a certain amount of airflow over the limit the ecu is programmed for, and will cut fuel to stop you from "over boosting". we adjust the delay timers and the percentages of the overall tables to get rid of this issue. and yes it does feel like hitting a wall with your car when it cuts fuel.

 

well its just weird that the car is doing it. im thinking the car must have had some kind of tune on it before i got it because why would a stock car not run right in the cold?

 

in the winter the air is colder and more denser and it will actually create more boost in the winter then it will in the summer time. so its perfectly normal.

 

so even completly stock evos right off the showroom floor will do this? thats odd

 

No they wont do it stock. You might have a boost leak, which in turn is making the turbo work harder to create boost pressure and causing an over boost issue.