ca18det coil packs

[purple180]

I have a miss @ 4000rpm. backfires when cold and struggles to rev past 4500 when warm. I have checked the resistance of every coil across the two left hand terminals and they are reading at 0.7ohms.when I try to read any other two combinations of terminals nothing can be read. they cant all be blown I read somewhere that these coils have a primary and secondary winding which i am assume works by having only the primary winding powered in low revs and the secondary winding powered at higher revs. So the secondary must have more windings and more resistance. My multimeter has a range of 2000Kohms and a resolution of 1Kohm so does anyone know how to tell if a coil pack is dead keeping in mind that the old pull the coil out and see if the engine dies trick doesn't work considering it idles fine when warm. plugs are all black as hell and considering it only overfuels for a short period of time (when missing) it makes it difficult to isolate the anomaly. Also if I would to the "look for sparks trick" i would have to drive down the road with my head out the window with no bonnet @ 4000 . tempting but probably wouldn't see shit and the old ladys down the road already have the cops on speed dial cause of me

[purple180]

Does anyone know anything about these??

[Z U L8R]

has it always ran like this or did this just start?

if it just started i bet it's a coolant temp sensor. logic behind that = u need more fuel when your motor's cold so it runs fine, car warms up but ecu still thinks the motor's cold so it's sending too much fuel.

the other possibility is wrong plugs/too wide gap.

ngk part#3330's bcpr7es@ .028 gap ftw

how much boost u running, what plugs and gap are in it now?

since you're good with a Multi meter you could always check the resistance on the wires going to your coolant temp sensor with the car cold...then check it with the car warm, and see if there's a decent change and/or compare retreived data to the correct values in the FSM.

gl
Dave =]

[Maxstyle]

maf maybe. Sometimes sr's and ca's go into this mode when the maf is bad. That might be the reason.

[racer98]

Originally Posted by purple180

I have a miss @ 4000rpm. backfires when cold and struggles to rev past 4500 when warm. I have checked the resistance of every coil across the two left hand terminals and they are reading at 0.7ohms.when I try to read any other two combinations of terminals nothing can be read. they cant all be blown I read somewhere that these coils have a primary and secondary winding which i am assume works by having only the primary winding powered in low revs and the secondary winding powered at higher revs. So the secondary must have more windings and more resistance. My multimeter has a range of 2000Kohms and a resolution of 1Kohm so does anyone know how to tell if a coil pack is dead keeping in mind that the old pull the coil out and see if the engine dies trick doesn't work considering it idles fine when warm. plugs are all black as hell and considering it only overfuels for a short period of time (when missing) it makes it difficult to isolate the anomaly. Also if I would to the "look for sparks trick" i would have to drive down the road with my head out the window with no bonnet @ 4000 . tempting but probably wouldn't see shit and the old ladys down the road already have the cops on speed dial cause of me

talk to the guys down at Quick performance in NZ.

[slownslurious]

I had a similar problem with my ca... I ended up bypassing the knock sensor, replacing the water temp, and the coilpacks, and it finally went away.
I'm not sure what the hell was wrong with it.