hotevo8

I have a 2003 evo that I just got and come to find that when you put the pedal to the floor(full throttle) when the rpms hit 3 to 3500 seems like the engine just cuts out and just shutters to beat hell, falls on its face. it doesn't normaly do it in 1st gear but 2nd and 3rd every time. any ideas????

evane

iTrader: (13)

have you changed your spark plugs? or done a boost leak test?

hotevo8

spark plugs timming belt ecm boost controler vaccum lines press sensor airflow sensor all have been replaced. no faults in ecu.

SLO-EVO

iTrader: (52)

boost leak ftl

hotevo8

checked rubber hoses not seeing anything boost press is 12 when starts to chugg but will reach 16 psi on full kickdown.

hotevo8

this is a stock evo with 60k on it. when i pinched off the wastegate solenoid line the shutter went away for awhile.

evane

iTrader: (13)

maybe it has something to do with the ECU controlled boost

hotevo8

thought so to when the solenoid has voltage applied to it it is then open venting waste gate press line. this always has 12v applied to it when key on and never cycles to 0v. so i replaced the ecu and press sensor (map) checked wiring to and from ok.

when i replaced timming belt i did notice that when i turned the crank to line up the cams by hand there would be alot of belt slack on the timming belt inbetween the camshafts. but whenn i run the engine then shut it off the belt is tight. could this be a timming issue??? I reall y appreciate everyone help.

Fast_Freddie

iTrader: (50)

When you did the timing belt did you take a breaker bar and turn the crank over by hand at least 2 times before starting the car in order to preload the tensioner? If not your belt may have skipped a tooth...

hotevo8

hey guys haha got it turns out it was a coil never knew it would have been just a coil misifiring under load. replaced the coils and don't have the hesitation anymore. I was thinking if It was that then i should have got a check engine light on. but i hear that these don"t monitor misfire ubove a set rpm??? who knew!!!!!! lots of money wasted but nevertheless thanks for the help.