So I'm trying to get my mspnp to work with my FE3 since I've only had it running on the stock ecu thus far, and it's only been run to check oil pressures and what not, hasn't been driven yet.

With the stock ecu in I have strong spark across each cylinder but when I try with the mspnp I only have spark coming from one coilpack. Obviously it won't run on the megasquirt, but it fires up fine with the stock ecu.

Anyone have any ideas why the ms isn't firing the other coilpack?? I've been away from this stuff for too long and I'm feeling pretty lost on this one lol.

 

I'm afraid I haven't been following your build, so a few random questions.

What sort of cam / crank pickups are you using with that engine?

When you say "stock" ECU- is that the stock Miata ECU or the stock ECU from the donor car?

Do you have access to an oscilloscope?

You say "Obviously it won't run on the megasquirt", however I'd think that even with one coil missing entirely the engine should still be able to fire up and "run" to some extent. (There are millions of two-cylinder, four-cycle engines in the world. Yours would just have some extra pumping loss.) If it's not even making an attempt to fire up and run, this makes me wonder if the problem is larger than simply one coilpack not firing. (Don't believe me? Disconnect one of the two coil primaries and crank it with the stock ECU in place.)

 

Just the person I was hoping to respond.

This motor uses a modified Cas from a miata, iirc I had to modify the disk inside it to fire a waste spark signal and other than that it's all miata hardware.

By stock ecu I mean the miata ecu, and yes of course the motor would run on only 2 cylinders lol not sure why I was thinking otherwise, the timing must be far enough out or something because it doesn't even fire with the ms in.

I don't have an oscilloscope but I could probably get my hands on one if necessary.

I've swapped coils, plugs, wires, and nothing changes, only spark off one pack with megasquirt in.

 

Update: Tried some new plugs, made a significant difference and I even got the ms to run for alittle bit after swapping ecus once the motor was hot. It was only running on one pack though so I shut it down to confirm and prevent my cylinders from getting to washed out. Can't get it to start on ms again, guess it was a one time only deal. That's all for tonight I think

 

MS is still only triggering one coilpack, guess I'll try another ms see if that helps..