this happens moreso, when my car is just started. if i'm just cruising in like second at like 2500rpms it is constant, and then it will kind of act like the engine is choking, and studder. kinda of like this "rrrrrrmmmmmm ugh ugh rrrrrrmmmmmmm" haha



best way to describe it.

what could this be? i was thinking new fuel filter perhaps, or just new sparks plugs once again.

does your car have a stock ecu?



mike

Not quite, Haltech

richen it up a tad, lean = flat spots , bucking. rich = stumbles



mike

whats the difference between flat spots, bucking, and stumbliing?

when the car is cold its very lean, and then once its warmed up it's rich and doesn't do it. so i guess i should just let it warm up a bit more



How often should fuel filter be changed, i was thinking mine more than normal, and it might just be good measure since i put oil in with my gasoline (2 stroke)

yeah, mine does this too, the coolant temp sensor is heats up faster than the engine, so it it lean and stumbly when its almost warmed up too. theres a correction map coolant temp vs fuel you may want to richen it up when its cold.



the fuel filter is cheap enough so that if you have any doubts you should just change it



mike

what kind of settings should i be changing on the haltech? just more fuel at colder temps, or is it self explainatory once i get in the program?

theres a coolant temp map, try bumping it up a little in the colder temps.



mike

OK, thanks for the help