V3.0 board - Ignition Troubles... I'm about fed up w/ MS!

[trwebb26]

I have a v3.0 board running MS&SE. Everything works fine except spark output. I started out having the VB circuit drive an MSD 6a - to an MSD blaster 2 coil - to an optical dizzy. The car responded VERY well for a few minutes, but would then start ignition misses and die. If you want a few minutes - it would start back up and run fine. There are several other who have had this problem that I've found on this forum and others.

After a bunch of searching - I figured out that I don't even need to use the VB circuit to trigger the msd box... I could just run off of the negative side of the D14 diode. I rewired the megasquirt - removing Q16 (the IGBT coil driver) and now the car don't respond like it is supposed to. I know that I'm getting spark because I CAN start the car... but the timing is WILDLY off - and it only runs on a few cylinders. My wideband O2 reads nothing but 10's (the minimum reading) and there are big puffs of atomized gas coming out of the tailpipe... It smells like raw gas BAD.

So I guess the good part is that I'm getting SOME spark. I've tried inverting the spark output, checking for cold-solder joints on the board, messing with the settings in megasquirt, several dwell settings (it is currently set at fixed-50%). At this point I don't know if I'm missing one little thing in the software, if my board is wired wrong, something is fried in the board, or what is going on. I'd appreciate any troubleshooting ideas as I'm about tapped out. Thanks!

[jsmcortina]

Yes, you can run D14 straight to the MSD box as shown on http://megasquirt.sourceforge.net/extra/setup-msns.html

Have you strobed you timing to see where it is? The changes in settings may require a change in trigger angle.

James