Ian C
23-06-05, 21:27
So. I had a problem trying to advance ignition timing on my car whereas others (SecondJump, Heckler, Alex) could do it fine. Dave S also had the same problem. Bizarrely, we could retard timing OK.
Turns out that we had both wired the ignition loom up linearly like this:
Channel 1 -> Cylinder 1
Channel 2 -> Cylinder 2
Channel 3 -> Cylinder 3
Channel 4 -> Cylinder 4
Channel 5 -> Cylinder 5
Channel 6 -> Cylinder 6
And it SHOULD have looked like this:
Channel 1 -> firing order 1 (cylinder 1)
Channel 2 -> firing order 2 (cylinder 5)
Channel 3 -> firing order 3 (cylinder 3)
Channel 4 -> firing order 4 (cylinder 6)
Channel 5 -> firing order 5 (cylinder 2)
Channel 6 -> firing order 6 (cylinder 4)
Dave S worked this out while I was away in France, I had no idea what the problem was, and I'm incredibly grateful to him for sorting an obscure electrical problem before I even started on it!
:thanks:
I've rewired my connectors and tested it and I can merrily advance my ignition timing now! :woot:
I have a theory on why the E-Manage would retard timing OK, it has three strategies:
1) no timing change - takes the signal in from the stock ECU and lets it's through to the igniter.
2) retard timing - takes the signal in, waits long enough for the required degrees to pass, then re transmits the signal to the igniter
3) advance timing - takes the *first* signal in and lets it pass but remembers the time it went off. When the next ignition event comes around the E-Manage predicts when it's going to fire based on the previous ignition event, and sends a signal to the igniter x degrees before the stock ECU send it's own signal. When the stock ECU sends it's own signal it takes it in and discards it, after monitoring it for changes from the last ignition event (to track changes in stock timing).
That is a hypothesis only. I am no more privy to the inner workings of the EM than anyone else here, but it explains why advancing the timing shows up a wiring order problem, whereas the other scenarios don't.
Anyway :yawn: :D and Good Work fella to Dave S.
-Ian
Turns out that we had both wired the ignition loom up linearly like this:
Channel 1 -> Cylinder 1
Channel 2 -> Cylinder 2
Channel 3 -> Cylinder 3
Channel 4 -> Cylinder 4
Channel 5 -> Cylinder 5
Channel 6 -> Cylinder 6
And it SHOULD have looked like this:
Channel 1 -> firing order 1 (cylinder 1)
Channel 2 -> firing order 2 (cylinder 5)
Channel 3 -> firing order 3 (cylinder 3)
Channel 4 -> firing order 4 (cylinder 6)
Channel 5 -> firing order 5 (cylinder 2)
Channel 6 -> firing order 6 (cylinder 4)
Dave S worked this out while I was away in France, I had no idea what the problem was, and I'm incredibly grateful to him for sorting an obscure electrical problem before I even started on it!
:thanks:
I've rewired my connectors and tested it and I can merrily advance my ignition timing now! :woot:
I have a theory on why the E-Manage would retard timing OK, it has three strategies:
1) no timing change - takes the signal in from the stock ECU and lets it's through to the igniter.
2) retard timing - takes the signal in, waits long enough for the required degrees to pass, then re transmits the signal to the igniter
3) advance timing - takes the *first* signal in and lets it pass but remembers the time it went off. When the next ignition event comes around the E-Manage predicts when it's going to fire based on the previous ignition event, and sends a signal to the igniter x degrees before the stock ECU send it's own signal. When the stock ECU sends it's own signal it takes it in and discards it, after monitoring it for changes from the last ignition event (to track changes in stock timing).
That is a hypothesis only. I am no more privy to the inner workings of the EM than anyone else here, but it explains why advancing the timing shows up a wiring order problem, whereas the other scenarios don't.
Anyway :yawn: :D and Good Work fella to Dave S.
-Ian