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Old 04-08-2014, 08:33 AM   #1
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Default Reverse firing order

The one assumption that I did not verify was the sparkplug order (not the firing order). I assumed, incorrectly, that plug 1 was closest to the firewall, so the plugs and injectors are wired 1-A starting at the firewall and 4-D at the waterpump. Yes, I know. For some reason that was just in my head. I have beat myself up already.

I am hoping to verify my thinking about how to remedy it. I prefer to NOT unsolder and resolder the 8 wires (spark and injector).

I am thinking that,in theory, I can simple reverse the firing order in MS and all should fire correctly. Is there a flaw in that logic?
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Old 04-08-2014, 09:23 AM   #2
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so rewriting code is easier than fixing 8 solders?


you also made more than 1 bad assumption that will cause you to have to go back and fix your wiring a second time...
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Old 04-08-2014, 09:35 AM   #3
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Originally Posted by Braineack View Post
so rewriting code is easier than fixing 8 solders?


you also made more than 1 bad assumption that will cause you to have to go back and fix your wiring a second time...
I don't know why it is rewriting code? In TS there is a firing order setup.
Not a big deal to resolder, just hard to get to.

What was my other bad assumption?
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Old 04-08-2014, 09:38 AM   #4
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That you should wire it like 1234 ABCD. hint the firing order in the MS software has no affect on anything.
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Old 04-08-2014, 09:49 AM   #5
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I think I see it now... "Firing order" is labeled A-H (could it be that corresponds to the Injector A-H)

Plug 1 is at the front, 4 at the rear.

Assuming firing order is 1432

Injector A correlates to Plug 1
Injector B correlates to Plug 4
Injector C correlates to Plug 3
Injector D correlates to Plug 2

Would that be more correct?
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Old 04-08-2014, 10:02 AM   #6
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the firing order is 1342, but yes, more correct.
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Old 04-08-2014, 10:04 AM   #7
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Correct, but the firing order is 1342
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Old 04-08-2014, 10:38 AM   #8
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Quote:
Originally Posted by Braineack View Post
the firing order is 1342, but yes, more correct.
I love the internet... I copied that order from a forum post...LOL

Now it looks like I need to wire:
Injector A correlates to Plug 1
Injector B correlates to Plug 3
Injector C correlates to Plug 4
Injector D correlates to Plug 2

So from front to back wire the injectors as: A D B C


Hopefully that will be all that I have to do for right now... I was expecting up to 25% rewire to fix mistakes anyway...
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Old 04-08-2014, 10:51 AM   #9
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Old 04-09-2014, 04:55 AM   #10
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If it's just your spark order can't you just swap the leads around ?
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Old 04-09-2014, 08:33 AM   #11
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Originally Posted by HeresJohnny View Post
If it's just your spark order can't you just swap the leads around ?
you could, but you'd have to be running seq. cops. and you'd have to build you harness like a retarded octopus to allow each lead to be able to connect to any coil.
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Old 04-09-2014, 09:18 AM   #12
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switch them at the coil pack end
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Old 04-09-2014, 09:23 AM   #13
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Quote:
Originally Posted by HeresJohnny View Post
switch them at the coil pack end
knock knock...
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Old 04-09-2014, 10:29 AM   #14
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Quote:
Originally Posted by HeresJohnny View Post
If it's just your spark order can't you just swap the leads around ?
Seriously? It would take less time to change it in TS and your hands wouldn't get dirty. Why kluge when doing it right is easier?

Where's the QCB?
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Old 04-09-2014, 10:55 AM   #15
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Originally Posted by DaveC View Post
Seriously? It would take less time to change it in TS and your hands wouldn't get dirty. Why kluge when doing it right is easier?

Where's the QCB?

he already posted, and you can't just *****-nilly change the spark order in that manner.

spark is always A-B-C-D-E-F-G-H.
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Old 04-09-2014, 05:50 PM   #16
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Default Timing?

That seems to help, I do appreciate everyone's help... Because my assumptions were totally off, I have lost a little bit of my confidence in my thought process.

So as I am not assuming anything, can you help me out with the initial timing... I have read the information below but have some questins...

Remove your injector fuse or otherwise ensure that no fuel will be injected so the engine cannot start.

From http://msextra.com/doc/ms3/checktiming.html:
Hook up your timing light and crank the engine.
Confirm that the timing is regular and that the reported advance matches the expected cranking advance.
If it does not then adjust your tooth#1 angle (trigger wheel) or trigger angle/offset (other spark modes.)
If the actual timing is more advanced than Megasquirt thinks, then increase the trigger angle/offset.
If adjustments of more than 10 degrees are required, making the change, Burn, key off and restart the engine..

Where do I find the "reported advance", is that the same as "trigger angle"?

The difference in the terminology is going to get me in the end. I understadn "retard" and "advance" but do not know which is a "+" and which is a "-" in TS.
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Old 04-09-2014, 11:00 PM   #17
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Checked timing and when megasquirt set to hold at 10* the engine read 10*
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Old 04-10-2014, 09:53 PM   #18
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Quote:
Originally Posted by Braineack View Post

he already posted, and you can't just *****-nilly change the spark order in that manner.

spark is always A-B-C-D-E-F-G-H.
I'm wrong, but it's OK because I look good.
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