I have recently discovered a problem when a secondary trigger signal is connected to the ecu but is not being used
- you mean sectrig disabled ?
- Yes disabled
- Are you sure "use secondary as primary" is NOT configured ?
- Yes not configured
- Did you reboot after disabling sectrig ?
- That has been tested
- is the relevant config in ... guessing ... [this zip] ? or forgotten ?
- This can be replicated on any setup quickly so didn´t bother with a config
- The results is that the trigger signal somehow makes its way to the primary trigger causing a LESS PTRIG error.
- but extra pulse in primary would more likely cause "too many PTRIG", right ?
- Yes, but of course secondary trigger should by no way make its way to the primary trigger input (think 2nd config set for wasted spark and disabled secondary cam)
- but extra pulse in primary would more likely cause "too many PTRIG", right ?
I set this up on the bench and recorded a trigger log turning the secondary input on and off. It��s very clear that the signal is occuring once per cycle. Also uploaded is when the secondary trigger is enabled so it´s clear that it´s the secondary signal.
Link : http://www.vems.hu/files/BMW/v3.3_u001609-2013-04-28-13.27.15.triggerlog
Link : http://www.vems.hu/files/BMW/v3.3_u001609-2013-04-28-13.33.04.triggerlog
If running sequential fuelling and secondary sensor has failed prior to cranking then there is no indication in Vemstune to the failure (no missing secondary and RPM=0, rpm showing that primary still works, only running flag "ON")
Ideally if either sensor fails before cranking an error should state so.
- RPM=0 states that something is wrong with the trigger setup:
- although the running flag, WBO2 heater and fuelpump ON can give some hint if primary trigger is still pulsing...
- In such case, someone can hardly avoid looking at the triggerlog anyway.
When running "Missing tooth primary allow sync without camsync recieve" the ECU cannot distinguish between strokes (of course: without camsync !)
- this setup is only suitable for wasted spark ignition (typically ignout repeats during the full cycle, like 2,3,2,3)
- this setup is NOT suitable for fully sequential ignition. Setting 4 different ignouts in a 4 cyl (eg. 2,3,6,7) is an invalid config without enabled (and working) sectrig (camsync).
- at best (eg. in emergency, not for daily use) the ecu will fire the sequential coils and with 50% chance of getting the engine running.
- Ideal would be that at any time when ecu has no camsync it will run dual out (If the ignition setup allows it) : that would be possible, although that will kill the ignition coils most of the time within months
- This is incorrect, I have seen COP´s been run for thousands and thousands of hard use kilometers being run wasted spark and they have not failed. This feature is available on a number of ecu´s.
. If you really want to limphome without camsync, set up the 2nd table/config (see TableSwitch and referred VT help).
- Does the ecu swap strokes in an attempt to get the engine running?
- no. With the proper config the "swapped strokes" would be the same ignout (or ignouts, in case of ign-dualout) anyway: (example repeating ignout configured as 2,3,2,3 ... in a 4 cyl, or 2,3,6,7,2,3,6,7 in an 8 cyl ), or 2-3, 6-7, 2-3, 6-7 with ign-dualout (but that stresses coils beyond design limits)
- again: the "non-repeating" ignout 2,3,6,7 ... is an invalid config in a 4 cyl without cam-sync. Although it might work to limp-home with it, it's not supported