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I am able to introduce FreeEMS engine #11, my 1996 GM 3.1L V6 engine...

It is using a Jaguar A3 board with FreeEMS-0.2.0-SNAPSHOT-99-gc76a4e0-DEV-EvenTeeth-Both-3and1.s19 firmware, using a flat 60% VE table and no ignition advance other than the 10 degree BTDC limp home mode built into the GM DIS module.

First run video:
http://youtu.be/rCacE4CE4R8
Watch for the flame coming out of the open header near the end of the video

Second run with pan around engine:
http://youtu.be/MM2kjRFz0No

TODO: Fred and I need to figure out the ignition advance to send to the DIS module...

EDIT: added car in title 03/13/2012

Once again, congratulations on your efforts and achievements! :-)

I have a few commits and documentation things to get out of the way, but getting you some advance really needs to be number one after those things, as it's not really functional until then. So this is my commitment to start developing a GM DIS specific decoder for you. I'll let you know when I start on it, hopefully within a week. You can test as I go, if that suits you :-)

Nice photo, too! :-)

Fred.

A photo of the car

Binary log file of the Deuce's GM 3.1L V6 starting and running with RPM increasing and decreasing.
Also has an engine restart after it died during falling RPMs.

Well! That certainly explains why it dies when you lift!

Load these:

• RPM
• Cam sync
• primary teeth seen
• secondary teeth seen

When your RPM is decreasing there are NO cam pulses coming in, so sync is lost via "too many primary pulses before sync pulse" mechanism.

If I had to guess, I'd say that the engine has a physical fault, but perhaps it's just the way that GM DIS works? If it works like that, we can handle it, but we need to understand why it does that and what it means. If it's not supposed to work like that, then you need to fix your engine :-) I thought you told me that the cam pulse was a direct signal from the distributor/CAS unit and not processed.

Let me know what you know so we can go forward from here. Once this is solved it shouldn't die anymore. It was dying from lack of fuel, which is what I suspected, though I thought from a lean zone, when really it was from total absence of injection.

Fred.

Here is the log from this evening's session after tightening the battery cables at the battery.
Have I mentioned the battery is under the car under the passenger floorboard? LOL

Still dodgy, and in the video you can see the LEDs go dark on the over run. Other signals look clean though. BRV is pretty stable, but a bit high, needs calibration. IAT and CHT are noise free. TPS is clean too. You get some bad packets, and always when on the throttle. Maybe a bad connection in the serial line with the engine vibrations? It looks fairly shaky in the video, could be shaking something loose. MAP is smooth, as is RPM.

IE, solve the comms interference and solve the CAS drop out and you're in good shape. The ball is back in your court :-)

Next time load up the log and check sync vs rpm vs secondary count etc before uploading so you can self-confirm that you've really fixed it. Save the upload cycle on your low bandwidth connection too :-)

Fred.

Log with new CAS

This time I warmed up the engine, then throttled up a couple of times...
More flames out of both headers and smoother idle.

Log after PNP USB mod

Perfect, good work! May the tuning begin :-)