i am attempting to identify poor/erratic running with a Toyota 4AG race engine using a Motec M4 computer. Almost every part on an around the engine is new, yet i have erratic operation which is sometimes on 1 cylinder and then it moves to another cylinder. i am using exhaust temperatures to work out which cylinder is not working properly. i have done extensive mechanical tests and ruled out problems from that source
i have been unable to work out how to make the scope view all 4 cylinders at the same time and separate the signals as they all seem to be vertically beneath each other??. is there a fix for this??
I attach various traces of the secondary ignition where i have changed the ignition coil as i suspected that as being part of the problem . i nearly all cases, the voltage rises. can anyone offer some plausible explanation for this?
what i can see is...
voltage varies a lot across all 4 cylinders despite having all new parts and plugs with identical gaps. changing coils increases the peak, but still i get this big variation. engine compressions are all identical
i changed the coil saturation time from 3 to 6 msec and that got it up to about 6amps and increased the peak voltage output. engine sounded better but still randomly not running nicely on all 4.
roadandtrack wrote:here are some files. any help appreciated
what i can see is...
voltage varies a lot across all 4 cylinders despite having all new parts and plugs with identical gaps. changing coils increases the peak, but still i get this big variation. engine compressions are all identical
i changed the coil saturation time from 3 to 6 msec and that got it up to about 6amps and increased the peak voltage output. engine sounded better but still randomly not running nicely on all 4.