erratic megasquirt timing

Megasquirt2 3.47 with hei8 ignition. ecu was set up by diyautotune for the HEI

trying to confirm base timing and trigger offset, but I have a feeling I screwed something up somewhere along the line....

following these instructions: https://www.diyautotune.com/support/tec ... se-timing/

my timing light is showing an oscillating timing number from 10-35 degrees independent of rpm or trigger offset with the timing locked at 10 degrees. this is warmed up to full operating temp. distributor is completely locked out with no mechanical or vacuum advance even in it. bare housing with a hall effect sensor and HEI8 module remote mounted on a heat sink.

what am I missing? have I screwed something up?
what else do you guys need to know?

While you're waiting for someone who's got more familiarity with this setup, allow me to step in a pile of the basic opportunities to miss something in the heat of "almost running" 

Did you hit "burn" first before "close" at the end of Step 3? (if you open the More Ignition Options dialog while connected, is "Fixed Timing" already selected for the "Fixed Advance" field?)

It sounds like you're confident that there's no physical advance happening, so I figured that seemed like the easiest opportunity to have MS doing something with timing when it shouldn't.

Might be time to upgrade. Lulz. 

Yessir.  I made sure to burn prior to closing that window.

And no vtec laptop for me. Using only the best. Cheapest laptop available at bestbuy on a random Tuesday. 

Is there another setting that could cause this? Or a wiring issue?

Are you seeing any advance at all that correlates to your table?  

In reply to dean1484 :

Maybe I have to double check the numbers when I get home tonight

If you disconnect the bypass ("B") pin, how steady is the timing? If it is still all over the place, make sure the pick-up coil is not wired backwards.

Will try this tonight.  

Ok, so brain dump time:

Ensured fixed iming was burned. Still fluctuating. 

Checked advance tables: no correlation. 

Disconnected the b wire. Holy berkeleying E36 M3.  The tack signal stopped bouncing.  Car stopped breaking up. Idle improved dramatically.  Finally revved clean to 5k and idled at the set 900 rpm. Timing light shows 20 degrees of advance for a commamded 10. No amount of trigger offset tweaking changed the 20 degree number.

Hooked b wire back up, car died instantly.  

What now?

Im sure i dont just leave the b wire disconnected.....

But its damn tempting now that ive finally heard this thing run RIGHT for the first time in years....

Did you check the MegaManual?

http://www.megamanual.com/ms2/GM_7pinHEI.htm

Or the the MSExtra Manual?

http://www.msextra.com/doc/pdf/html/MS2V357_Hardware-3.4.pdf/MS2V357_Hardware-3.4.html

http://www.msextra.com/doc/pdf/html/MS2V357_Hardware-3.4.pdf/MS2V357_Hardware-3.4-69.html

http://www.msextra.com/doc/pdf/html/MS2V357_Hardware-3.4.pdf/MS2V357_Hardware-3.4-108.html

I suspect you may have a setting incorrect as the info from DIY is fairly generic and isn't specifically for the HEI system.  Verify your settings using the firmware you are using (whether stock MegaSquirt or MSExtra) and follow the links I provided.

Settings are exactly what is in the 3rd link.

Bypass on d16 wired straight to the hei8 module.

https://www.diyautotune.com/support/tech/install/mopar/megasquirt-vintage-ignitions/

Could this be the solution? Its a mopar lean burn distributor coupled to a hei8 module. Diyautotune set the ms2 3.57 up for hei for me.

So do you have the distributor with the dual VR’s?

There certainly could be an issue there.

Single vr, no advance whatsoever.  Standard early 80s lean burn distributor. 

Hei8 module from a tpi camaro. Standard parts store stuff. 

So as long as it is wired properly and configured properly in the firmware, I’m not sure why the timing would be erratic, unless there’s a dirty signal going to MS from the module.

The disconnect of the B wire indicates there is an issue.  Do you have any spares?   Sometimes modules or VR sensors can fail without fully failing.

I will double check the wiring again. Ive found some references to using a relay on tbe b wire, but nothing consistent. 

I have swapped distributors and modules multiple times up to this point. Be more than happy to do it again if it'll help. 

I want to make sure that im understanding this correctly.  With the bypass pin disconnected, the megasquirt has no control over timing, and its running purely from the module.  Right?

Right.

So that means that it HAS to be in the megasquirt program, right? If its running purely from the module, the wiring/components are good.

Right?

I don't use the HEI (or TFI) module to do ignition output.

I use the HEI as a signal source and use the native BIP373 in the MS for spark out.

You still have the limitations of a "Basic Trigger" but loose the smoke and mirrors of compelling the HEI to do your bidding.

You can leave the HEI in place as it provides a logic level signal that is less susceptible to noise than a VR signal.

Can you explain a bit more about that to me? Maybe a potential solution here

Basically you add a component (BIP373) to the MS to directly control the coil (or coils if you add more than one BIP373) and the VR or Tach signal goes directly to the MS as usual.

https://www.diyautotune.com/support/tech/other/bosch-bip373-ignition/

The only question I don't know the answer to with your solution, is what firmware you are currently using.  That makes a difference to what settings to use within TunerStudio, etc.

http://www.msextra.com/doc/pdf/html/MS2V357_Hardware-3.4.pdf/MS2V357_Hardware-3.4-75.html

You are not using an HEI distributor, and you have a 3.57 main board you don't even need the HEI module at all. HEI modules were used as a way to add ignition output to a v2.2 main board that did not have ignition output on board.

Your v3.57 board has a very robust ignition output driver already installed (Q16). Using the native output of the MS gives you full control of the ignition and fully supporting all of the MS ignition features. The biggest plus is spark cut is available using the native driver. I don't think the spark turns off on an HEI install (I think the timing just goes to base)

For single coil output you would use Section 5.3.1.1 of the Extra manual.

To eliminate the HEI module, Follow the manual for setting your main board up a VR input. See Section 5.2.2  of the Extra manual.

Both of those sections of the manual give the appropriate settings needed in Tuner Studio.

You can read through Section 6.2 of the Extra manual for the distributor setup if needed.

If you want to retain the HEI module for input leave the input connections and settings alone.

NOTE: I'm Not sure how a Relay board does with a VR input, so you may need to keep the HEI module for the non-VR input signal. (if you are using a relay board)

Read and follow only the sections of the manual that apply to your setup, this will simplify the instructions and help avoid confusion.

RE: firmware, you should be using the latest version of extra 3.4.2

Since i had the ms2 3.57 configured by diyautotune for hei, will these instructions allow me to eliminate it? 

You also mentioned using the hei module for input. What benifits/downsides to that? Im really hoping to avoid wiring changes, as thats a huge job on a wire tucked pro touring car.

Ill need to see which version of the firmware im using.  How big a job is it to change to the newest?