Ignition problems:
Making a BMW 325 turbo we did see the ign sliding up to 60 degrees (2000-9000 RPM).
- One test is made by using a "smart" strobelight but they can see exhaust manifold glowing red at 3000 rpm so the ign is moving (Vt is stable at ca 20 degrees)
Another bench test made by me using a scoop. Ch 1 measured the trigger 60-2 and ch 2 measured ign out. I see ign at 24 degrees after the missing tooth at 2000 rpm. At 9000 I see ign 36 degrees before the missing tooth. Vt is stable at ca. 20 degrees all the time.
Think I have seen this years ago but cant remember what cores that.
Any clue?
- measured how ?
- a smart strobelight can show similar symptoms (especially when fooled by wasted spark)
- or measured via scope ?
I did make a bench test and get the same results
Any idea how this can happen?
Log and config
http://www.vems.hu/files/MembersPage/PeterJensen/bmw/bmw_v3.3_u003404-2011.04.22-17.42.04.zip
http://www.vems.hu/files/MembersPage/PeterJensen/bmw/bmw_v3.3_u003404-A-2011.04.22-17.46.40.zip
short quicklist
- VemsTune validate
- Sometimes it's sg. very basic setting misconfigured that can cause this
- toothwidth = 6 deg ? reftooth 0,40,20 (from top to bottom) ?
- next trigger tooth = 20 ?
- nr of ign outputs, etc...
- definitely it is a good idea to try upload the correct configlet from bottom of "primary trigger dialog" and see if it helps
- i259 used for idle pwm, at 250hz, dual channel pwm IAC
- it worths a test with lower freq, or even disabled
- knock retard disabled ?
- although that would show up on VT gauge
- per cyl spark delay ?
please review these and reflect. We can review and benchtest the following working day.