DTAForum.com - a forum for the DTA ECU

You are right! Having a scope trace on the field would be really beneficial for diagnostics. Not so many have own dyno where take a trace when something peculiar happens on full load and high revs. I can't plug a scope when I drive on silent industrial area trying to debug the f..king system.

x30xe wrote: ↑Wed Aug 03, 2022 11:28 am I'd still be curious to understand what the "filter" setting does and what is the theory behind it. I understand that some of the settings are hard to explain for the ECU manufacturer and they perhaps do not want uneducated "tuners" to mess with settings... but anyway.

Which filter setting would you like explaining?

stevieturbo wrote: ↑Wed Aug 03, 2022 11:44 am I just wish all ecu makers would incorporate a scope that records a trace when it has come across errors, or just an ability to view a proper scope trace of the crank/cam patterns.

At least then it gives you a proper visual to try and diagnose what about it is making the ecu unhappy.

Without a scope trace, you're largely working blind.

or of course you can hook up an external scope to see.

It's not as easy as you think.
The T Series does have the hardware to do it, but it's currently not fitted as the first iteration was affecting the crank signal that it was trying to measure. It needs more development to work, so that's something for next year.

Alex DTA wrote: ↑Thu Aug 04, 2022 2:43 am

x30xe wrote: ↑Wed Aug 03, 2022 11:28 am I'd still be curious to understand what the "filter" setting does and what is the theory behind it. I understand that some of the settings are hard to explain for the ECU manufacturer and they perhaps do not want uneducated "tuners" to mess with settings... but anyway.

Which filter setting would you like explaining?

Gap tooth factor ... sorry confusing with the word "filter".

Manual says

GAP TOOTH FACTOR
The missing teeth are detected by the time difference from the previous tooth. The gap tooth factor determines how much bigger the missing tooth time is before it is recognised as a missing tooth. This can be determined by cranking the engine and using the crankshaft oscilloscope. Clicking on the missing tooth in the oscilloscope display will tell you how much longer the missing tooth is than the tooth immediately before it. Standard factors for 1, 2 and 3 missing teeth are as below. Clicking on the “Set to Standard Button” will set to these values automatically. Sometimes it may be beneficial to increase or reduce these.
Missing Teeth / Gap Tooth Factor
1 1500
2 2000
3 3000


In what circumstances the missing tooth time deviates from the normal tooth? I'm trying to figure out when is the right situation to alter this setting.

Gap tooth factor is used only during the synchronisation. Once the engine is running, it's no longer used.

Because gap detection is time based, where the gap is in the crank rotation will change the "size" of the gap.

If the crank is at a constant speed, the time between each normal tooth will be the same.
If the crank is accelerating, the time for each tooth will be smaller than the previous tooth. This will be just after TDC
If the crank is decelerating, the time for each tooth will be greater than the previous tooth. This will be just before TDC

The same applies to the gap.
So the gap tooth factor is used to allow for this apparent change in the size of the gap.
It's not used much. It is only really required on engines with a very small flywheel where the gap is not in the ideal location, which is the gap passing the sensor as the piston rises to TDC number 1.

Thank you! Clear explanation.