Bizarre Trigger Angle Issues
 

I'm helping a friend (thebeerbaron) setup an MS-II on his 95. We're using MSextra 2.1.0q. We are able to drive the car without issues, but the idle is very low. We've tried fiddling with fuel and spark, but no real solution. We suspected the trigger angle may not be correct, so we got out the timing gun and quickly observed what is approximately 10 degrees ATDC. That's not good.

So we used the trigger wizard to advance the timing 20 degrees. This quickly put the timing to the base 10 we wanted. So we burned the setting to the ECU. Checked the timing again without changing anything and it's right back to 10 ATDC. WTF?! Opened up trigger wizard again, verified that it's at the new setting. Yep. We then repeated the advance of 20, verified timing, burn, back to 10ATDC.

We're lost. Any thoughts?
Thanks!

you put 'fixed timing' back to 'use table'?

what basemap are you using?

Nope. Fixed timing @ 10. The base maps are DIY Autotune's.

does the 'trigger angle' under 'tach output/ ignition settings' match the 'trigger wizard' numbers?

Yes, and it updates correctly when we modify the value via the wizard.

When the timing reverts the the incorrect 10 ATDC, the value does not change. Example. We started at 62, took it to 48 to get it at 10 BTDC. After burn, timing's back at 10 ATDC but the trigger angle is still 48. We could then take it to 30ish. That gets 10 BTDC, burn bzzt, back to 10 ATDC. Rinse, repeat.

It smells like software, but I just can't really believe that.

it's late and I'm drunk, but now that I'm happily ensconced in my hotel and finally have teh intarwebbs, the only thing I can think to add to what Mike has said is that we tried setting the trigger angle with both MegaTune and TunerStudio. Every time we hit burn, the god damn thing jumps back to 10ATDC.

this does not compute.

The trigger wizard is broken*, I encountered the same problem once you burn it reverts back to where it was only with a greater trigger angle. Makes no sense.

Easy fix on a MK1 though, don't use it, just rotate the CAS

*http://www.msextra.com/forums/viewto...=35263#p240273 3rd paragraph.

Thanks! That post makes sense. I think our troubleshooting should be to try the remedy in the post first then maybe go back to 2.0.0?

We thought of the manual adjustment with the CAS, but unfortunately, we run out of adjustment WAY before getting close to 10 BTDC.

My '93 was set with 2.x.x and I have since moved to 2.1.0 without issues, so maybe once it's correct, no worries about upgrading.

makes me wanna go back out and check mine...

2.x.x is a dead end, update to 3.0.3r and pester to get it fixed instead

I'll spare you all the machinations we went through to get it timed properly and just let you know that we ended up having to cut the CAS bolt slot to allow it an extra 1/4" of travel towards the advanced side.

Any software we trick we tried worked until the burn button was pressed. We tried values all over the place, burning them, cycling power, etc. etc. etc. SAME base timing always came back.

Getting the CAS to physically go far enough was the only solution we found. It's now running like a champ and thebeerbaron is on his way to fun roads with TunerStudio's Autotune on. Wish him luck!

Thanks for everyone's ideas. They were all excellent, albeit not exactly right.

I have this exact same issue with my DIYPNP. Changing the trigger angle does absolutely nothing. I have it set to fixed timing 10 deg, I can change trigger angle from 45 to 95 and the marker on my crank pulley doesn't move a single bit. Ideas before I rotate the CAS?

Said fuck this shit, moved the CAS, fixed issue. Now my car doesn't feel like a pile of ass!

Wait what? I just adjusted the timing now after mucking around with the intake cam gear. Didn't have any issues with the DIYPNP running 3.1.3 beta. Used the trigger angle wizard. Rechecked it after a while, was still good.

Maybe the issue is fixed in 3.1.3?

Let me rephrase that- I've never seen this issue come up. I started with 3.0.3u

album, you have 3.1.2, this is a non issue with that firmware. not sure what your deal is.

3.0.3u was/is loaded on mine.

Sorry to necro my own thread, but I'm finally getting around to installing the MegaSquirt again and am running into the same exact issue.

Does anyone know when or if this software issue has been fixed? I'm using the MS2 extra 3.2.1 release now.

Same symptoms - set timing in trigger wizard, all is perfect, hit burn, the value sticks in TunerStudio but the actual timing jumps back to where it was before...

pretty certain that was fixed a few years ago :)


so you're saying as soon as you change the trigger angle value to sync the timing when looking at your timing light, then hit burn, the timing move back out of sync?

I'd really have hoped so and lost an hour fooling with this assuming it was my fault. Probably still is, but seems a lot like it wasn't fixed.

Precisely. Got the car idling, and the timing marks on the pulley were extremely retarded, back about where the belt leaves the pulley. I would open the trigger wizard, adjust it (audible difference in idle), get the two marks to 10 and T (idle was stupid fast at this point), the instant I hit burn, there was an audible shift in the engine note and the marks were back at the belt departure point. The value I set in the trigger wizard would appear in my Trigger Angle/Offset field under Ignition Options. At various points in the day, I had anything from 35 to 80 in there and the marks on the pulley were in exactly the same spot (after a burn).

I eventually gave in and moved the damn CAS, but I was hoping for a software solution. I like to be able to fall back to the OE CPU as easily as possible.

I flashed this firmware version recently and I thought it went through OK. I looked at my mainController.ini file and the "signature" value is "MS2Extra Serial321 ", so I think the firmware is the version I stated...

Any ideas?


edit: 100% stock 94. And yes, I'm an idiot.

It's not fixed on my car, and yes that's exactly what happens. The car moves back out of sync by the same about, but at the 'new' trigger angle.

It's shite, but I live with it as once it's set, it's set. I just move the CAS instead.

if that's the case, that's what I'd do. But that's crazy, do not like.

Ha, I guess as long as this has been necro'd, is it worth upgrading my firmware? I can't seem to find a change log.

Edit: DIYPNP (3.0.2 iirc)

yes, for a start you'll remove a pretty nasty part throttle bug which causes a stumble.