Weak signal on Trailing Coils !?
 

Hey guys... I was getting my fd ready for this years season ... Removed the engine, cleaned up the enginebay ...installed a new Flywheel as my old one had cracks on the surface ... and on and on it goes.. How ever i put everything back together and tried to fire it up but it wouldnt start as a result of low battery and worn starter motor.... changed the starter motor and the battery but it still would not start... sometimes it tried to but died out pretty fast so i guessed i had it flooded.... after trying to deflood it the whole day i just gave up as i was becoming more and more upset and just did not have the nerves to keep going today....

I checked the ignition as i installed a msd ignition box and a twin tower coil for the leading plugs.... just to make sure i didnt mess anything up in the wiring but the leading coils do have spark.... trailing coils however dont... the positive signal on the training coils is working the negative is not or sometimes very weak! Any ideas what and how to check next? I have had cold start issues ever since my single turbo conversion and Emission stuff removal as i also removed allmost every valve and gimmick that is not essential for track use.... I also encountered some ignition problems on high boost thats why i went for the msd....

Now im thinking that the trailing coils where getting a poor signal ever since and i was running on leading only.... ?! Bad wiring loom? CAS sensor? But my tach seems to work when the car is running ! Any help would be apreciated otherwise ill rip the whole wiring loom out tomorrow again and rewire the whole stock ignition system...

Setup:
Holset HE500
Power FC
850 primary inj.
2000 sec. inj.
twin fuelpump
MSD 6al-2 Ignition box
MSD Twin Tower coilpack (leading coil)

do you still have the idle air control valve? and are using it?

nope deleted it...

Ok fixed it! Sometimes when people do stupid things :D... like i did! I painted the coil bracket and forgot that it was grounding the coils.... so took some sandpaper and sanded it down to bare metal on the groinding points... and car fires up just fine!

Good thing I came across this. I just painted my bracket :facepalm2:

Are you sure the coils are grounded through the bracket? While there's a metal tube to prevent crushing the feet, the coil feet look like they are just part of the plastic case. Unless there is a ground wire inside the feet that connect to the metal tube, but i doubt that.

Regardless, i will sand my brackets just in case

Yes Im 100% Sure because while as installing my msd 6al-2 and twin tower leading coil i had some isues and tested for spark with the oem leading coil to see where my problem was and when the oem coil wasnt grounded it wouldn spark! when grounded on the left side, just one side of the coil would fire and vise versa!