Megasquirt Support Forum (MSEXTRA)

hello all

I have a misfire and a stumblbue at idle. I have been working on my fuel table but i have come to realise its an ignition problem.

I have an edis4 coil and module.
from what i understand its non adjustable in a programming sense. I have heard it may be
a capacitor in the megasquirt?

I have a clear RPM signal
I have done a tooth log and its clear and fine

any ideas fellas ?

have included a log :}

Can you post the MSQ that goes with that log?

Ken

i have included the current tune.

its supercharged with a sc12 I have edis ignition and a vacuum operated air bypass valve from a late model mini.

The first thing that jumps out at me is.......

Dwell Type should be set to Fixed Duty (NOT Standard as you have it) when running EDIS!

Ken

thanks for your reply mate. Have tried a few different settings. I have fixed the dwell in the log I have attached to this post.... still no improvement

just to add. when I received my ecu the chipset had been dislodged and it was rattling around inside the unit.

I had messed around inside the box and re-fitted it. I think i even put it in back to front initially.

is there a part in the box that relates directly to the dwell settings?

cheers

mini-dunger wrote:is there a part in the box that relates directly to the dwell settings?

Dwell is irrelevant with EDIS. The module controls timing and dwell based on the signal sent from the ECU.

Use a strobe to make sure that the actual strobed timing matches what you are seeing shown in TunerStudio.

James

thanks for your reply

i have had the timing fixed the whole time as I have been tuning the fuel side.

the timing light is the same as what tuner studio is telling me.

You cant tune fuel if you have a flat timing table, the fueling requirements will change when you enable spark advance control.

Read the manual and follow the instructions to the letter for EDIS usage.

However, I would not use the EDIS module as it does not allow MS full control of the spark.
The EDIS trigger wheel and sensor in addition to the EDIS coil are great parts to use with MS.
MS support of EDIS is a legacy holdover from MS1 and a v2.2 main board that does not natively support ignition.

rickb794 wrote:However, I would not use the EDIS module as it does not allow MS full control of the spark.
The EDIS trigger wheel and sensor in addition to the EDIS coil are great parts to use with MS.
MS support of EDIS is a legacy holdover from MS1 and a v2.2 main board that does not natively support ignition.

AMEN!!!

Ken

thanks for your replys

I understand that the fueling requirements will change with a timing map based on the table.

I also understand the complexity of tuning. My timing advance will be all in by 3000rpm and limited to around 25 degrees. So fixing it at 25 and developing a base tune at this isnt as stupid an idea as it sounds.

regardless of the fixed timing and any other aspects of my tune the dwell is doing something entirely incorrect.

We all feel your frustration!

But, as James pointed out above,

Dwell is irrelevant with EDIS. The module controls timing and dwell based on the signal sent from the ECU.

Hence, Rick pointed out,

However, I would not use the EDIS module as it does not allow MS full control of the spark.

Then I jumped in and agreed with both of them!

There is simply no way (that I'm aware of) to measure (or control) the dwell that the EDIS module is applying!
That is one of several reasons why I abandoned EDIS, years ago. I wanted full control of the various ignition functions.

I will now get my big nose out of this thread and go back to my corner.

Ken

EDIS can work fine, but as I said, the Megasquirt has no control over dwell and any "dwell" it reports is meaningless.

James

I am using EDIS 6 with module and the engine runs awesome with all kind of crazy dwell numbers.

As James said, ignore the dwell numbers as they are irrelevant.

As rickb794 said, turn off fixed timing and build a timing map or you will have to retune everything.

David

hello again all

thanks for your help.

I purchased my ecu on the advice that it was plug and play for edis4.

none of the internal mods have been done.

So i ran the wire jumper wire today and it still runs the same. Still has a stumble at idle and an even worse stumble at WOT

i have changed plus up and down the heat range, closed plug gaps, opened plug gaps....

I thought I had it sorted and then it would die as if it was blowing the plugs out...

the miss seems to be only on 1 and 4 which are on the same bank of the coil..


oh man

it also hunts really bad....

Hunting is often caused by being too lean at idle and with the fuel PW fluctuation. Add some fuel to that area (say in +5 steps) and see if that helps. I have found that adjusting cells to keep PW to a steady number helps too - this will mean that in the idle area, VE numbers go down as you move up the table.

James

thanks for your help mate..

I have included a photo of what I am trying to work with

Where are you injecting? It's impossible to see in that picture and you don't mention it in your previous posts. You know that the siamese intake port setup on the Mini engine has some peculiarities when it comes to fuel injection, right? The fact you have trouble with the outer cylinders might be due to that and not ignition.

Jean