I'm having a part throttle hesitation/misfire...

Its bascially in lower rpms, if i'm driving around 2,500rpms it will start and i'll continue to add more gas but nothing really happends, then all of a sudden the car jumps forward and the rpms go up really quickly...

so, hesitation starts, i add more gas, after a second the car jumps forward and hesitation stops.

only in part throttle, at wot, drives fine

only happens in closed loop driving...in default open loop it drives perfect...

i have a/f gauge, i'm not sure how accurate it is but this is what i've noticed: when the hesitation occurs it goes all the way into red, which is lean...after giving it more gas and the rpms go up and it stops, it quickly jumps to green, which is stoich

on fuel pressure gauge, if hesitation occurs while crusing at around 40psi, after giving it more gas and it will jump back to normal at a little higher fuel pressure...

had the car hooked up to a computer at a mechanics: all the testing was done with the car idling and revving up.

left injectors pulse either rate/pressure is about .5 -1.5 off...lower then the right bank

when it was temporarily programmed into a service fuel mode or something like that. it revved up a lot smoother and didn't hesitate...

i'm thinking its something with the tuning, fuel map wise. but i'm wondering why the left injector pulse rate is so much lower than the right. i was told that you can't change this using tuner cat which is what was used to tune the car.

its a heads/cam lt1...

 

another thing to add: i've had the heads/cam setup about 4 months. after the car was tuned it ran really good for about the first 3months and recently started acting up...

 

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