That if you've bolted/screwed down (or simply letting touch) your Megasquirt to a metal surface in your car, you've created a ground loop through the housing, which I've proven can create resets and can also create random tach (and other sensor) spikes.

If you're suffering from this situation, throw a towel or something undeneither your now un-mounted Megasquirt, and take it for a drive!

Figured as much, I coated mine with rubber undercar coating spray. Well the "feet" at least.

Apparently the v2.2 board is completely isolated from the housing. The v3 board however is not.

This may be the sole reason people arn't having problems with the v2.2 board, but do with the v3 board.

I'd be weary about just the undercoating as protection, if you have metal screws clamping it down (over time it may ground out).

post pics of where you mounted your MS unit!

Ill admit it, I have not bolted it down. Its so light that I just Strapped it down.

Interesting Joel. This explains why i have never noticed any noise. mine is velcro taped down so it is isolated.

Originally posted by Star Turbo Talon
Interesting Joel. This explains why i have never noticed any noise. mine is velcro taped down so it is isolated.

yup. same here.

You can see where mine is mounted here.

http://www.mysterymeat.net/kard/phpAlbum/main.php?cmd=imageview&var1=Summer+2006+Build%2FIMG_0552.JPG&var2=1

Note... this pic has the MS hard mounted, I had the problems. It is now held in the same spot with a *generous* portion of industrial strength Velcro (use the velcro dual-loc, if you REALLY don't want it to go anywhere).

Well I know everyons says it doesn't happen on v2.2 boards but I am getting some bad tach spikes. I will try this but does anyone know what usually causes the tach spikes in the v2.2 board?

I think only one person noticed tach spikes in the v2.2 board and he claimed it was he internal ignitors. No one else has had that issue on the v2.2

Terry

If you got noise on your v2.2 I'm willing to bet, it's your ground spot (take it directly to battery), lack of capacitor on your +12v to ign coil, and/or lack of car stereo filter on your +12v to your Megasquirt.

This stuff isn't needed if you're running 100% no problems.

Well, here is some more confirmation. My V3 is hard mounted and I did experience tach spikes before changing the input circuit. I guess I'll put some rubber isolators on it.

Corbin

'95 ESI-T
Now with more power and fewer leaks



Gimme fuel...Gimme fire...Gimme that which I desire

I told the guys on the MS forums and Phil, one of the admins, is adding my find to the MS manuals!

I hope we can get a new 2GNT 'squirter to try the v3 with the standard, simple install, and see if they get spikes when their module is isolated.

Well when i tested the few I made, there were no Tach Spikes but I wasnt running spark either.

Terry