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Timing gauge is not sync with the table on Idle

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Old 12-20-2016 | 01:49 PM
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Default Timing gauge is not sync with the table on Idle

Hi All,
I recently installed my new MS3X on my 04 miata.
I noticed that on idle the timing gauge is between 7-9 while the table is set to 10, when i rev it up a bit it seems to by synced.

I had the initial timing set by a tuner, i don't know if it was ever synced or it recently became un-synced.

Before i will find myself a timing gun, i tried to play with it a bit, to see if i can effect those numbers.

I followed the following steps:
1. fixing the ignition timing to 10 - > burn -> close and open the acc (truing the key off and on)
2. open the trigger wizard and adding 2 degrees -> burn
3. changed it back to use the ignition table ->burn -> close and open the acc

After i have added 2 degrees there wasn't any change, the timing gauge is still between 7-9

does anyone have an idea what could it be?

I have added some pic for reference and my project.

At Idle
A bit of rev


My project is in the link below:
http://dl.dropboxusercontent.com/u/1...8_19.21.29.zip


Thanks,
Rom.
Old 12-20-2016 | 03:00 PM
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DNMakinson's Avatar
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You don't understand the purpose / function of the fixed advance.

Put in Fixed Advance. Set to 10 degrees.
Go to the Wizard.
Set up a timing light to see the ACTUAL timing of the car on the harmonic balancer.
Adjust the offset in the Wizard until the timing marks are at the same 10 degrees you have fixed.

Now the MS matches the engine.

That is the purpose.

The gauge will always match the table unless you are using separate Idle Advance, in which case the gauge will match the Idle Advance.
Old 12-20-2016 | 03:14 PM
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Post tune. You probably have an idle advance table.
Old 12-20-2016 | 04:32 PM
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Originally Posted by DNMakinson
You don't understand the purpose / function of the fixed advance.

Put in Fixed Advance. Set to 10 degrees.
Go to the Wizard.
Set up a timing light to see the ACTUAL timing of the car on the harmonic balancer.
Adjust the offset in the Wizard until the timing marks are at the same 10 degrees you have fixed.

Now the MS matches the engine.

That is the purpose.

The gauge will always match the table unless you are using separate Idle Advance, in which case the gauge will match the Idle Advance.
I understand the purpose, but as i mentioned before i want to see if i know how to change the number that the gauge displays...my issue is that i advanced by 2 degrees and the gauge remains the same.

I below is a pic from my idle advance and its seems to be off.

Old 12-20-2016 | 04:49 PM
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Idle RPM timing correction is on.

Also, no you don't understand the purpose.

The timing gauge is the commanded timing. Its when the megasquirt thinks it is firing. So turn off idle rpm timing correction and it will follow the table.

When you added 2 degrees it changes the calculations for when to fire. You need to read the basic startup guide.

Procedure is as follows.

Set fixed timing to 10*
Check timing with timing light
Adjust the trigger wizard until the timing light reads 10*.
Burn
Set back to table.
Old 12-20-2016 | 05:42 PM
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OK. It is possible, as your last pic shows, to not be using idle table, but still be using idle advance correction, which changes idle timing according to how far off actual RPM is from target RPM.

Still, as we both have said, changing the timing offset will not change what MS is doing. However, it does change what is actually happening to the engine.

Put another way:
You tell MS what to do via tables and corrections
MS tells the engine what to do
The gauge is just information to you of what MS is commanding (it is not feedback)

Possible corrections to the timing table:
Idle table
Idle correction
High MAT retard correction
Low CLT advance correction
Knock retard
Those are what comes to mind.
Old 12-20-2016 | 05:47 PM
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Keep the fixed timing on 10 while you use your timing light and if the timing light says 10, you're good to go. If you want to check anyway after you switch back to "use table", check the gauge in Megasquirt, rather than the timing table. The gauge will show the actual commanded timing advance after corrections and such are factored in.
Old 12-21-2016 | 01:59 PM
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Thanks a lot guys, the gauge displays 10* according to the table.

It was the "Idle RPM timing correction" and the "MAT retard correction".

Now i will just confirm that the marks on the pulley are aligned (should be a a tuner did it).




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