Sync Error @ 4300rpm

[Hanzie M48]

Hello,

when the RPM goes above 4300, I get a sync error. I'm using a M48Pro

I can see in de screen the rpm starts hunting around at 4300rpm, it goes to 2000-12000 etc etc. Then I get the sync error.

I have checkt the sensor signal(with a scope) on pin 6 and 27 (Mag-sensor), I can not see a faillure!
The voltages of the sensor are;
1150rpm = +/- 2,65V
2000rpm = +/- 4.08V
3000rpm = +/- 5.88V
4000rpm = +/- 7.77V

Further I have looked into the General setup, ref sensor type. When I select 2,3,4 it makes no difference. On 5 the engine will not start.

When I select -1 the max volt is only 4500mV, This is not the solution.

The resistance of the sensor is +/- 492Ohm. Is this too low?


Also I have checked the camsignal, (1 tooth per enginecycle with a Hallsensor). The pulses are very short, but ok I think. Does Motec only counts the pulses or does it also look the pulse-time???



Thanks in advance.


Hans

[Hanzie M48]

Is there no one who can help?

I have been thinking of what could be the problem. Crank index position? Too close to TDC? Maybe the ECU hasn't enough time to calculate then?

Tomorrow rotate the trigger disk and adjust the Crip.

Hans

[bbs16]

How I understand it works is the Motec looks for a certain trigger level voltage on the sine wave when its got this it is "armed" and looks for the point when the wave crosses the 0v line. this should occur between two ref signals (on multitooth setting for trigger wheel) what sync % are you seeing? if it changes much could be stretch in belt or chain?

[Hanzie M48]

Hello bbs16,

Thanks for help!

The sync% is 32. I don't know what that maen, 32% of what? (In the ''help'' I can read that sync edge must occur in 180 +/-70 degrees before the indextooth). The engine has a chain (BMW S14 Engine).

I have set the index tooth to 324 bftc, and the problem is gone. No sync errors at all when I rev the engine now.

Hans

[bbs16]

So sounds like youve sorted it out then? good news.
Running same engine as you an S14 bmw. using a 12 tooth crank with hall sensor and the M5 mag on cam. the 32% is where the sync postion is relative to the two ref trigger points ie in the middle if it was 50%.

Regards Andy.

[Martin]

This will be good reading on this subject

viewtopic.php?f=11&t=240&st=0&sk=t&sd=a&start=10

[ButtonPusher]

Mate did you get your issues sorted? I have some expeirence with Motec ECU's on S14 2.3 and 2.5lt Slide and butterfly BMW Group A and DTM engines.