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The diode is added in the ECU for the ISV. Still need the flyback from the AFM power to the fuel injector power.
Do you still have the ignitors connected? I am very sure they need to be.
I will remove the diode for the ISV. The flyback is wired to pin 3 of the AFM connector. I believe it was a green and red wire, I can confirm tomorrow.
The VEMS unit has 8 built-in transistor coil ignitors, I'm running wasted spark matching channels 0+1, 2+3, and 6+7 to run the two coil packs. I have removed the stock coils along with the dual distributor and blocked it off with the plug you provided.
If not already done, check the power lead to the coil packs. I think that was part of the wiring harness. If I remember correctly, the stock igniters had to be there in order to get power to both coil packs.
I wired the coil packs directly to the BK 2.5 or rather, 2x BK 1.5 leads that connect to the stock coils. I capped the GN and GN/RED as I completely bypassed the stock ignition control units. Did I screw this up?
Edit: I should add that I added two inline 5A fuses on the hot lines to the coil packs. I started with 3A but they eventually blew.
Last edited by sotothehail; 09-01-2015 at 05:53 PM.
Reason: Added info and resize image
Wish I could help, but I am not sure. I am sure someone else can chime in. I just remember Raceboy saying that the car running over there on coil packs had the stock ignition control units still installed. However I am not sure they were doing anything since it really depends on the wiring to the coil packs.
Do you have a spark checker to make sure that that you do have spark?
Yeah, I was using a timing light to make sure I was getting spark. I was getting spark intermittently between cleanings of the plugs, that's why my assumption is that too much fuel is fouling them. I had the car running for several bouts, but it would not hold idle on its own (will test again after removing IACV diode and possibly swapping to new spark plugs).
Did you change the fuel reg value on the base engine setup. I never installed the coil packs so not sure what the value was set at. I think original map was set up for larger injectors. So the value needs to be set for the 19 lb injectors. The help screen gives a formula that should get you close.
Wish I could help more on the coil pack setup. I just never got that far. The coils are brand new.
And using this calculator (with pressure adjustment), I have calculated all sorts of flow rates -> req_fuels, varying from 20 to 15ms. But that was still way too high and I get way too much gas unless I lower req_fuel to around 6-7ms. I have read on the VEMS documentation that: "It is common practice to then half this number and to double the values in the VE table, as this means that the VE table's resolution effectively doubles and allows finer grain tuning." Maybe this is the case?
Tomorrow I'll double check the cal files i have but I think at idle you should expect to see instructed injector duty of around 2.5ms with std injectors. The latency will probably be between 0.5-1.0ms.
With a typical idle ve of say 15% and idle map of 55kpa you would get, leaving the other fueling calc adjustments to one side, using your req fuel of 20ms * 0.55 * 0.15 you get 1.5ms + latency.
If the injector flyback isnt connected correctly the injectors cant shut quickly and it will over fuel. If peep built yours is like mine you need the 12v pin at the afm to connect to the 12v feed for the injectors.
If the injector flyback isnt connected correctly the injectors cant shut quickly and it will over fuel. If peep built yours is like mine you need the 12v pin at the afm to connect to the 12v feed for the injectors.
Yes it does need the flyback. Where did you connect the 12v feed for the injectors? I had connected it to the pin of the large connector (cannot remember pin number) inside the rear fuse box.
I may have miswired my flyback for the injectors. I assumed it would be sufficient to wire my flyback to any of the R/W wires going to any single injector as they are all connected to the same source. I will rewire my flyback to the source.
I am not sure what you did is really a problem. I did connect my flyback to pin 8 on the connector but I was not really sure how the flyback works and wanted to connect directly to the power feed. Somebody that understands this connection should chime in.
The config that Peep sent me for a 380cc injectors (running a distributor though that shouldn't make a difference) has 13ms required fuel setting, that's set to even fire.
Edit: I've just looked at the VE map Peep gave me and the VE at idle is more like 45% which would backup the idea of halving the req fuel and doubling the VE and make the calculation of the 13ms more plausible.
Edit2: the more I look at this the more it looks like it depends how you set it up in VEMSTune - the numbers are all relative and the calculations may be meaningless - I'd contact Peep, maybe send him the config ask his advice.
I am not sure what you did is really a problem. I did connect my flyback to pin 8 on the connector but I was not really sure how the flyback works and wanted to connect directly to the power feed. Somebody that understands this connection should chime in.
You could think of the little coil in the injector like an energy storage device, when the injector is turned on the thing charges up, when ecu switches the injector off (by disconnecting the ground) it wants to release that energy at a high voltage (flyback) to quickly allow the injector to close but needs an electrical path to do so. The flyback wire and the components in the VEMS provides the circuit to do that. There are a few different ways of handling flyback voltages, this setup happens to be VEMS's way. The isv is a coil too and behaves similarly to an injector (and needs flyback handling because it is also switched using PWM) timing isn't as critical as the injector PWM so with VEMS you can use a simple diode to allow the voltage to "freewheel" in a loop through the isv coil which wouldn't work well enough for injectors but works fine for the isv.
09-01-2015, 02:22 PM
