CThompson

Hello,
so after engine machine work, forged internals, and megasquirt 2 assembly I started my car last night! It was just for a second but I have a question for you guys. Almost every time I turn my key to the on position I get a loud audible popping noise from the coils. Do you guys have any idea? The car runs so I wouldn't think there would be a setting or wiring issue but I'm not sure. Its a 1997 1.8 (1.9 technically) Thank you!

Blysccr

OEM coils?

CThompson

Yes, OEM coils, pretty new too. Probably 100 miles on them. I wired the megasquirt up myself so I just want to make sure I don't have a problem on that end

Blysccr

Gotcha. I’m having a similar issues with my flowforce coils. Ms3. Sometimes I turn the key on one coil will hum and get very hot. Other times nothing.

Haven’t had time (or a motor) to diagnose.

I entered the new info for the coils onto tunerstudio but hard (for me) to tell if the root cause is the same?

CThompson

Have you checked if you're spark output is inverted or not? (Going high or going low) the fact that your coils are getting hot make me think maybe its set to the wrong thing so you're sending out a ground signal and it's not happy

Blysccr

It’s only on 1 coil maybe 30% of the time the car is sitting with ignition on playing around in tuner studio.

would something like that affect them all or just one?

CThompson

I don't see how the spark output would cause that issue then. I believe if you had the setting wrong it would fry the coils instantly. I wish I could help more but If I come across anything more ill let you know

Blysccr

Yeah man same here. I should have the take off coils from mine if you’d be interested.

Ted75zcar

iTrader: (2)

Make sure spark output is set to going high

Nicolas L

look up the improved spark circuit here or somewhere. It uses a TC4427 or something like that (I don't store electronic component names in my head that well).
It's an old *** problem that's been fixed 20 times.

EDIT:
Holy **** I can't believe I remembered that name. Many times I go to the garage and as I'm opening the door I already forgot why I was going there.

Here you go: https://www.miataturbo.net/megasquir...t-83247/page2/