Big backfire on MS3 , attempt to startup the engine.

[ponthai]

the relate post http://www.msextra.com/forums/viewtopic ... 31&t=58510

now I try startup the engine. but it does backfire on the exhaust so loud like the gun.
I setup the advance to 10 degree on the table. it can not run. Its died again.

I think about this problem, Its maybe more advance the ignition and more fuel.
Please advice me.

This is my msq.

2015-05-20_08.52.41.msq

[kjones6039]

I setup the advance to 10 degree on the table.

Have you confirmed that setting with a timing light?

Ken

[ponthai]

I setup the advance to 10 degree on the table.

Have you confirmed that setting with a timing light?

Ken

Yes confirm already.

And I does recheck ignition again by setup 10 Degree advance and see the mark it correct mark or not.
I sees the mark at 10 degree for confirm.

it maybe wrong by I plus the 360 degree, or not? Now my setting 611 degree. or I try 251.

[ponthai]

I start it again find lost sync again and Big back fire.

I adjust before and not loss syc show in the composite logger. But when I starts the engine, it have sync and unsync.

Please advice me to tweak the vr.

2015-05-26_10.10.45.msl

2015-05-26_11.32.48.csv

2015-05-26_11.15.13.msq

[Matt Cramer]

The composite log you attached does not see a sync and unsync problem or any indicator you need to adjust VR trim pots. Please try making a much longer one, at least one minute of attempted starting.

[billr]

"Big back-firing" is almost always a problem with ignition timing or cross-fire, so let me ask a few questions:

Why are you using "LEDs" for spark output if you have the MS3X board? Can you get six spark outputs from "LEDs", to support the "COP" set? Have you checked spark timing at all six cylinders, to be sure they are all fairly close, not just #1?

[ponthai]

The composite log you attached does not see a sync and unsync problem or any indicator you need to adjust VR trim pots. Please try making a much longer one, at least one minute of attempted starting.

ok sorry i found unsync and sync in the composite looger when I try start it.

i will try 1-2 min start for longer log.

[ponthai]

"Big back-firing" is almost always a problem with ignition timing or cross-fire, so let me ask a few questions:

Why are you using "LEDs" for spark output if you have the MS3X board? Can you get six spark outputs from "LEDs", to support the "COP" set? Have you checked spark timing at all six cylinders, to be sure they are all fairly close, not just #1?

I using the led spark with TC4427. I using the Audi cops VAG low logic spark coil. it is not support with MS3X and i modify a little to DB15. I checked all spark and confirm it correct work.

[billr]

Did you use a strobe light on all six cylinders, or just test spark in TS test mode?

[billr]

I just looked at the TC4427 datasheet, can't the MS3X spark drive those just as well as the LED stuff??? Your choice, of course, but it would have saved some modifying of the mainboard and maybe save some confusion about which it "spkA", "spkB", etc.

[ponthai]

I using the TC4427 on MS3 for spark Audi coil and MS3 for Injector. I think that first big mistake to plan this project.
First I plan to using the standard coil for running. But when I change to the Audi Coil, everything change.
I read and do it like the ms3 manual.






and jump the all pin to circuit TC4427 and 5 volt supply.
I am not confuse the spark A B C D E F. It wire to the coil directly not through the MS3X.
In image the other jump wire on the other side of board.

[ponthai]

I found the problem.
I start the engine, when it sync signal it have double trigger. Such as normally 1 cycle have 6 trigger.
when it sync 1 cycle have 12 trigger Please the image.
first image before signal sync see have 6 trigger per cycle.
when in sync double trigger happen and lost sync.

try start2015-05-28_15.54.46.msl

try start2015-05-28_15.49.59.csv

try start 2015-05-28_15.54.30.csv

[Matt Cramer]

It's seeing too many teeth. Try adjusting the VR trim pots for less sensitivity or using a 10K resistor inline.

[ponthai]

It's seeing too many teeth. Try adjusting the VR trim pots for less sensitivity or using a 10K resistor inline.

Thank so much Matt. I try it asap.

[ponthai]

Finally I using 10K resistor. This is the logger and image of oscilloscope.
I found the signal after the process change
i try to change the config to Rising (normal falling).

please help me.... I confuse so much.
Can i use this trigger?

2015-06-03_08.20.12.csv

rising 2015-06-03_08.26.50.csv

Before

[Matt Cramer]

First composite log looks fine. Second is corrupted and I can't seem to open it.

[ponthai]

First composite log looks fine. Second is corrupted and I can't seem to open it.

see in the picture , can I using the last image for trigger?

[Matt Cramer]

The picture looks OK.

[ponthai]

OK, I check the timing light and BTDC change to 675 degree. And check everything working and prefect.

I try to start first start have the big backfire again.
so this my log data and my msq file.

I am hopeless to start my engine, isn't it?

2015-06-04_19.47.58.msq

2015-06-04_19.26.36.msl

[billr]

Did you ever check ignition timing on all cylinders?