Running with MSv3.0 29q2 code with 6 VB921 directly driving 6 coils. Trigger is by 36-1 wheel.
I seem to have stable RPM input (~250 during cranking). LED test shows that primary side of coil is being triggered/grounded by VB921 properly - LED flashes during crank.
But, I have 2 strange problems -
a) The plug does not spark during cranking. I'm using 6ms dwell for cranking
b) As soons as I release the key (cranking-> ignition on), I can see the plug then arch for a LONG time as in ~1.5 seconds. It looks like a long, continuous & powerful discharge.
Why does it happen? And only when I go from cranking to ignition on?
Datalog does show that as soon as I release the key, MS sees RPM jumps to ~700 rpm for ~1.5 seconds and goes into ASE & WE mode.
Any idea how do I debug this?
thanks./
Help with Strange Spark situation
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I think something is wrong with the wiring of the VB921.and/or coils.
The 1.5s long spark is almost certainly a series of sparks, the flyback triggers another spark.
Make sure the coils are powered off the fuel pump relay. This will ensure they are off when MS is off and on when it should be sparking.
Make sure you have good grounds from the VB921.
What do the LEDs do during this extended spark? Do all coils do it?
During crank are you seeing the LEDs flash in sequence. They should go from right to left. With short flashes and off most of the time.
(The sequence is D14, D16, D15, D14.... so you should see the 16,15,14 bit)
James
The 1.5s long spark is almost certainly a series of sparks, the flyback triggers another spark.
Make sure the coils are powered off the fuel pump relay. This will ensure they are off when MS is off and on when it should be sparking.
Make sure you have good grounds from the VB921.
What do the LEDs do during this extended spark? Do all coils do it?
During crank are you seeing the LEDs flash in sequence. They should go from right to left. With short flashes and off most of the time.
(The sequence is D14, D16, D15, D14.... so you should see the 16,15,14 bit)
James
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My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
James,
Umm - the coils is powered off the "ignition-on" circuit while the fuel pumps also have an additional switch thru the MS per the instruction. So, I can definitely move the coils.
The front panel LEDs are definitely though it looks like they are flashing from left to right and its a pretty constant cycle (like 1-2-3-1-2-3 as opposed to 1-off-off-2-off-off-3-off-off). The flashes are very visible - does it mean its likely too long?
I'll have to try & report back about the 1.5s & LEDs.
Any suggestions as to where to start looking if you suspect the wiring is wrong?
thanks.
Umm - the coils is powered off the "ignition-on" circuit while the fuel pumps also have an additional switch thru the MS per the instruction. So, I can definitely move the coils.
The front panel LEDs are definitely though it looks like they are flashing from left to right and its a pretty constant cycle (like 1-2-3-1-2-3 as opposed to 1-off-off-2-off-off-3-off-off). The flashes are very visible - does it mean its likely too long?
I'll have to try & report back about the 1.5s & LEDs.
Any suggestions as to where to start looking if you suspect the wiring is wrong?
thanks.
[quote="
Make sure you have good grounds from the VB921.
[/quote]
Forgot to address this - I am using a dedicated 14 gauge ground wire from the VB921 to the coil and the ground at the VB921 end is grounded to the chassis via 2x14 gauge wires and MS.
My VB921 are in a different enclosure than the MS - it sits directly above it via a short (3") umbilical chord - the 680ohm resisters stay with the MS. The +12V is fed via a single 10 gauge wire.
Make sure you have good grounds from the VB921.
[/quote]
Forgot to address this - I am using a dedicated 14 gauge ground wire from the VB921 to the coil and the ground at the VB921 end is grounded to the chassis via 2x14 gauge wires and MS.
My VB921 are in a different enclosure than the MS - it sits directly above it via a short (3") umbilical chord - the 680ohm resisters stay with the MS. The +12V is fed via a single 10 gauge wire.