fusion-turbo

On a timing light in the dark (now i can tell), my terminal L-1 on the leading coil will intermitantly fire when L-2 is supposed to fire. Every second or so ill see a mark on the underdrive pulley go from TDC to 180* AFTER TDC, when the L-2 terminal is firing, right?

What the hell would cause this? CAS? Leading Coil? How can i remedy this!

fusion-turbo

^

j9fd3s

iTrader: (3)

its supposed to do that. L1 and L2 always fire at the same time

fusion-turbo

Arent they 180* apart from one another? How do they fire at the same time??

Wyznewski

It's called a wasted spark ignition system. There is no gas/compression in the rear rotor when the front is firing, and vice versa. It doesn't hurt anything. You can even swap L1 and L2, and the car will run the same. However, the trailing plugs aren't set up like that, so no T1-T2.

fusion-turbo

Well how many sparks (per terminal) are there per rotation of the underdrive pulley? On the trailings i see one spark per rotation each, but the leadings are different.

My L-1 fires intermitantly at 180* (i guess wasted spark) once every second or so, while L-2 fires every single time. My L-1 is also very irratic while trying to read it, by that i mean the light will speed up and slow down, pause, hesitate and all that while on the L-1 terminal

fusion-turbo

Ok so i took off the black top on the CAS and checked to make sure it was alighned and it was.

*Note* this whole procedure is done while slightly retarded (in both the timing way and mental )

I put the timing light aimed at the CAS when on the trailing coil, and it checked out. One firing 180* after the other reliably

Then i put the light on the leading coil while on the CAS. The L-2 terminal fired on at both 180* incriments reliably, but the L-1 terminal was wierd... first of all i couldnt even get a reading from the timing light with the magneto close to the coil itself, i could only get a spark reading if i placed the magneto thing close to the spark plug (odd??) While reading it, i would only get a spark on the initial *TDC* postition of the CAS, and an intermitant spark on the 180* mark every second or so while L-2 did it every time. Sometimes it would "switch" and just fire on the 180* mark for a few times, then switch back.....

When i advaced the timing past TDC, it would ONLY fire at once (at TDC) and not at the 180* mark at all. As soon as i would retard the timing to exactly TDC or below, it would begin firing at both marks again....

HAILERS

Read until you understand at least ten percent: http://www.teamfc3s.org/info/articles/demystifying.html

HAILERS

Then read ten more times til you understand it all.

fusion-turbo

I understand how the whole system works now, thanks HAILERS

I guess what was really confusing me is that my timing will change on its own. I adjusted the timing slightly retarded today (@about 800 rpms), took it for a drive and it began detonating. I came back and now my car was idling at 1500 rpm's, checked the timing and i was running about 20* ADVANCED. (and yes, i tightened down the CAS before driving )

Then while i still had my timing light on it, my engine rpm's suddenly dropped to normal idle and my timing went back to being a few degrees retarded... out of the blue.

How can the timing adjust itself?