help!! my ka wont rev past 4 k....

[santi]

sometimes.. other times it just stutters at 4 k then goes right past to the red line..i'm pretty sure it's an electrical thing but i cant pin point it .. i've done wires plug cap and rotor.. i havent done the coil b/c it costs 140 or so for the mitsubishi style that my car came with.. this problem usually only happens when i run the car hard(at the track) or when i end up sittin in traffic for a while and the car doesnt get much air...other times the car will stutter and not rev in first gear .. but in second it'll go strong...my car was automatic and i did the swap but it never used to do this till recently..(3 months) so if anyone has any ideas please post .. or if you need more info just ask.. thanks

it's a stock twin cam 91

[santi]

no ideas?

[s14 2510's]

Did you try un pluging your mass air flow and see if it changes. My car wouldnt rev past 3.5k and it was the mass air flow. I have a couple good ones around my shop that should work if yours is bad.

[santi]

well i didnt try it on purpose but it did come disconnected at one point at a track ..and stalled right away.. hooked it back up and it ran semi normal again..so i think that works like it's supposed to

[santi]

sorry forgot to thank you.. so thanks for tryin

[240SicknessX]

whats your timing at? what do your plugs look like? any hints of detonation? what gas are you running?

[santi]

i run the cheap gass.. my plugs are about a month old..and i've never timed the car.. but how would timing affect the car sporaticly.. ..b/c sometimes it does run right.. (right when i first start it ) this only happens once the car gets warmed up

[240SicknessX]

i run the cheap gass.. my plugs are about a month old..and i've never timed the car.. but how would timing affect the car sporaticly.. ..b/c sometimes it does run right.. (right when i first start it ) this only happens once the car gets warmed up

i was thinking about the ecu pulling timing but im really off with that conclusion, damn it and you have changed your plug wires....... you replaced your plugs last with the correct heat range?

did you change the coil wire? have you checked the connection in and out of the coil?

maybe someone can help with this, what are the voltage leveles before and after the coil suppost to look like, 11-13 volts before and the same after correct?

[santi]

all those wires and plugs been done.. it is an auto ecu.. b/c i did the 5spd swap though.. thanks for tryin though..

[240SicknessX]

check the volts going into and out of the coil, that should be a good indicator if your coil could be goin out on you. check when its revvin fine and when its screwin up, see if you can swap coils with another car for a lil bit.