I have switched from a megasquirt to a Vems but have now problems with the trigger signals.
Primary and camsync trigger is hall.
Vems cannot properly detect trigger sequense from Nissan 300ZX hall module with 12-1 triggerwheel.
Car is race V8 engine, high compression and cranking at approx 80..113 rpm. The cranking rpm varies very much due to the high
compression.
When turning distributor by hand with ocsilloscope connected there is no doubt where missing tooth is. Allways 11 tooths between the
missing tooths and the camsync signal comes on triggertooth 0 (first tooth after missing tooth)
I have also tried disabling camsync all together, but it makes no difference.
When turning the distributor by hand (approx 80..100 rpm in vemstune) sometimes the sparkplugs ignite.
The rpm signal in vemstune (1.5.24) seems to be very stable. No flickering rpm signal.
Triggerlog when engine is cranking.
http://www.vems.hu/files/perboddum/cranking.triggerlog
Triggerlog when distributor is driven by hand
http://www.vems.hu/files/perboddum/turnbyhand1.triggerlog
http://www.vems.hu/files/perboddum/turnbyhand2.triggerlog
Vems config
http://www.vems.hu/files/perboddum/setup6.vemscfg
Picture of triggerwheel 12-1
I really need some help to get this Vems setup to work.
Per i have reviewed your triggerlogs and indeed the periods between teeth seem very irregular.
1) Lets start out with with following, could you make a triggerlog of engine cranking 8-10 seconds without injector and ignition fuse to verify if the irregular periods are caused by some noise issue.
2) Secondly could you make another triggerlog (again 8-10 seconds) but then spinning the trigger not by hand but by some something with stable rpm (perhaps use a battery powered drill), that way we can verify, if with stable RPM the trigger periods are even.
If you upload both these triggerlogs to your memberspage i will review and provide hints on how to proceed.
Best regards, Dave
Thanks Dave
Scope of triggerwheel 12-1 with power drill at approx 110 rpm
I have done some more test with power drill (50...120 rpm) and the distributor connected to Vems.
Vemstune displays the rpm but as soon as rpm drops and then gains rpm again I often get PRI.trig error in Vemstune and the sparkplug stops sparking.
It seems to me that it is a combination of low rpm AND varying rpm at the same time that confuses Vems.
I can have steady 60 rpm and there are no trigger errors and the sparkplug ignites
Tomorrow morning I will try install the distributor and make the logs
MembersPage/PerVolvo - Volvo 960 VEMS