Randomly resetting ms3x

[93supercoupe]

Hey guys, having a little issue. The car ran great all last year, never an issue. Car came apart for the winter and the MS was never touched. I installed a new clutch, bigger fuel pump, catch can, ect.

Now, i will randomly get sync loss, reason 0, and the SecL resets. High RPM, above 220KPA.

Nothing electrical changed since last year, exept now im running more boost (because i now have a clutch that holds it)

Any things is should look out for? Would a too large plug gap cause this? It runs very clean until the SecL reset.

[93supercoupe]

Knocked the gap down to .025 from .030 and it got alot better, but will still do it sporadically. So im obviously on the right trail.

Now im thinking this. I run a non resistor R5671A-8. Its a recessed tip type plug.

I was thinking of running a bkr8eix. Extended tip type plug, iridium, resistor, and the same heat range. But im not sure if going from a recessed tip to extended tip will effect the tune.

[Matt Cramer]

[93supercoupe]

Heres a log and the tune

[Matt Cramer]

I would try swapping to resistor type spark plugs - non resistor plugs are pretty unforgiving when it comes to noise issues.

[prof315]

I agree with Matt. I have seen non-resistor plugs cause all sorts of strange and random behavior with MS. The NGK extended tip iridium series spark plugs (EIX) are awesome. But what is the factory heat range for your engine? An 8 series might be a little cold at 20psi with water/meth injection.

[kizzoalfa]

Hi,

I had problems with Shadowdash install as well with non resistor plugs. I changed to NGK iridium resistor types and the connection became stable. With non resistor plugs SD lost connection just after engine started.

I also recommend going to resistor built in plugs. The non resistor ones have very high radiated EMC noise what get conducted via harness to MS and can cause reset.

However it would be good to know what is the cause of the reset.

For example if low voltage reset enabled in the uP config than it can be one.

Based on schematics there is no device connected to MS uP what can cause reset over the Low voltage interrupt. It looks like the uP getting the noise via its ports what can cause reset.

Zoltan

[93supercoupe]

I agree with Matt. I have seen non-resistor plugs cause all sorts of strange and random behavior with MS. The NGK extended tip iridium series spark plugs (EIX) are awesome. But what is the factory heat range for your engine? An 8 series might be a little cold at 20psi with water/meth injection.

Thats a very good point. Ill pull one today and see what the strap looks like. Maybe ill goto a 7. Typically id be running a BKR7 at this power/psi, but i got caught in the hype and just ran what was suggested to me.

So general consensus- Going from a recessed tip to an extended tip shouldnt change much as far as the tune is concerned? I wouldnt think it would, but i could see how it could, if that makes sense, lol.

Thanks for all the feed back.

[prof315]

You might be able to pull a degree or 2 of timing overall because the spark will be closer to the middle of the combustion chamber but the chamber shape and basic plug location will effect that a good bit. For example, if you run a non-extended tip plug in a hemi type chamber that had extended tip plugs as the OE plug, the spark will actually be partially shrouded and probably need more advance than originally. But on a wedge head it might not matter at all whether the plug has an extended tip or not. Or it might not be able to run an extended tip due to possible interference with the piston.

[93supercoupe]

You might be able to pull a degree or 2 of timing overall because the spark will be closer to the middle of the combustion chamber but the chamber shape and basic plug location will effect that a good bit. For example, if you run a non-extended tip plug in a hemi type chamber that had extended tip plugs as the OE plug, the spark will actually be partially shrouded and probably need more advance than originally. But on a wedge head it might not matter at all whether the plug has an extended tip or not. Or it might not be able to run an extended tip due to possible interference with the piston.

Thats kind of what i was thinking but i didnt know the specifics like you explained. Thanks!

It may be best i leave it be until im ready for the dyno again. Gotta upgrade the map sensor, throw these new plugs in and some other things and shes ready.

[93supercoupe]

still having random SecL resets. Started using BKR8EIX resistor type NGK's with no change. Its now beginning to do it at cruising and in boost, where as before, it was specific to only when boosting.

Not sure what i should be looking for, or how to even properly go about diagnosing it. BattV shows consistent voltage. Not sure what else i can do? Any ideas?

[Matt Cramer]

Next check - where exactly is the MS3 and everything wired to it grounded?

[93supercoupe]

I have all the grounds from the main board and MSx going to the factory harness ground location found on the strut tower. A singular connection for all the grounds.

[Matt Cramer]

That's not a very good ground point, even if it is what Ford used. It's better to ground to the block or heads, or better yet, the battery.

[93supercoupe]

Id like to ground to the battery, except its the trunk of the car. I can bring the ground to my block ground easy enough. It will take an additional couple feet to make it there, but that shouldnt be an issue