Can someone explain (timing related Q)
 

https://img196.imageshack.us/img196/...coldtiming.png

Can someone explain why the car should have MORE timing when the Coolant Temp is cold?

The percentage modifier gets applied to the timing table - so once the car is warm we have 0% of whatever is in the table...

Forget that they are called EGR - I think thats plain wrong...

This might explain my car knocking when cold, especially if its adding 9* of timing at 2000rpm

Cheers
D.

According to what I have read, the engine tries to get as high EGT after starting as possible (via increased timing) to get catalysator quickly to its operation temperature to have best catalytic efficiency.

I think if you run test pipe, you can set the increase to 0. You can do it with catalysator as well, but environment wil suffer ;-)

Right on the money!!{thumbup}

I think its timing retard puts more heat in the exhaust. There are cat efficiency tables that retard the timing when the engine is cold. This same cold engine ign advance table is in the CT9A ROMs. Perhaps cold engines need more advance to create a more complete burn. At any rate, I find it comical that both advance and retard tables exist.

I just asked the same question and I got very much the same answer.

Exactly...

I will have to look up the coldstart tables and see what their conditions are..

I know I've told you this already, but mine does the same thing (knocking on load transition when cold) and I've been trying to get rid of it for months, driving me crazy.

Tephra can you get that table(s) for my rom?

55590107 (Your 2010 RA Tephra ROM)

EDIT: I have the main one:

<table name="EGR Timing Advance" address="57359" category="Timing" type="3D" swapxy="true" scaling="Timing">
<table name="Load" address="61778" type="X Axis" elements="9" scaling="Load"/>
<table name="RPM" address="6175e" type="Y Axis" elements="10" scaling="RPM"/>
</table>

Another question:

I've been curious about the table labeled "Ignition Warmup Retard" in the Evo 10/RA roms.

With it set to "timing" scaling they read positive timing, with it set to "Min Timing" they read negative timing. The Defs currently out have them as "timing"

Tephra, do you know which is correct?

I was always under the impression that this was an absolute value that was mathematically applied as a subtraction to timing... but maybe I'm thinking about the other table.

Yea it would be nice to know what it is. If you set it to 0 with "Timing" then it's -20 with "Min Timing".

I want 0, not -20 so I would like to find out for sure.

emailed...

Give me the address of the table your talking about and I will look it up...

What he said.

I just looked this up, in your ROM its all 10's right?

The scaling is Timing, but what happens is that under certain conditions the ECU interpolates between this map and the regular timing maps.

After about 50C it doesn't use this map at all...

Isn't this the map that controls that?

(for the 2010 maps)

<table name="Percent Low Temp Timing Trim vs Coolant Temp" address="561bc" category="Timing" type="2D" scaling="Percent255">
<table name="Engine Temp" address="61310" type="Y Axis" elements="8" scaling="TempFarenheit"/>
</table>

Maybe when cold the engine needs a bit more advance to bring heat in and seal the piston rings bring the pressure up and up to operating temp a bit quicker. Or when the engine is cold it can't ignite fuel as well with lower timing.

No that is another one..

https://img687.imageshack.us/img687/...ompensatio.png

Sure its overly simplified and doesn't explain WHY, but at least we know it does it :)

:thumbup:

Got another table:

https://img842.imageshack.us/img842/...ccumulator.png

This one seems to be linked to a MAFHz Accumulator, absolutley no idea, but it looks like it is activated when the MAFHz accumulator sees 1800 grams of air (yeh weird)

I havn't worked out the interval for the collection period yet...

Well I think that map is ONLY used when the engine isn't upto temp yet...

So we can pretty much ignore it :)

https://img9.imageshack.us/img9/2175...ngcompensa.png

This one is VERY interesting, there are two tables, but they look similar.

I am not really a fan of the +20*..

Seems to be applied when Actual MIVEC Exhaust is greater or less than the value in the map...

Might be the source of our low load knock bryan?

ok... There are 4 tables, 2 for Intake 2 for Exhaust MIVEC.

Basically the ECU works out if the Actual Exhaust MIVEC is less than or greater than the Map Exhaust MIVEC.

Same for Intake MIVEC

Once it chooses which table to get the data from it then multiplies the actual difference by whatever the map lookup results in then divides by 0xA00

THEN it applies that as an ignition timing compensation...

ie, if you had 5* different between actual and map for the exhaust then it would be:

(5 * 32) * (whatever is in these 4 maps, ie 20*) / 0xA00 = 1.25*

so your timing would go up or down 1*

now this doesn't seem to be very much, but I just dont like the looks of these 4 tables:
https://img571.imageshack.us/img571/...vecoverrun.png
https://img560.imageshack.us/img560/...vecunderru.png
https://img101.imageshack.us/img101/...vecoverrun.png
https://img823.imageshack.us/img823/...ecunderrun.png

The values just seem so random, 20 with 0's on either side...

I am thinking of zero'ing out these tables :)

Hrmm

Bryan your maps are already zero'd out.

I emailed you the def's..

a quick look at 52690022 shows they are similar to mine.. as is 2011 Au Evo.

MR vs GSR same thing almost..

Why the difference for RA vs Evo??

Different cams stock?

Every time I change that table it ends up triggering a P050B

That sure looks just like the cold ignition retard table(s) from Evo 8/9

Does it idle better when cold?

When I zero out that table, my car runs a ton better in the cold when ECT < 120*F.

Yup works great on evo 8/9.

I put it back to OEM values on my RA because I was sick of getting the CEL.

Do you not get a P050B? The RA's seem to get it when tweaking that table.

No I don't get it. I did it to a 2010 RA that I'm tuning. He is running an AP. I don't think he is throwing any codes. I'll double check.

Just checked.. no CEL after a week or so.

I agree, I think zeroing out this table would be beneficial.

I see now need for these random values or how they would actually help at all... :thumbdown

Interesting, how do you have that table set?

I changed them for the RA Basemaps and everyone that used it started getting P050B's, but it back to OEM values and all gone.

All 0's.

In my car, I run E-85 and when the ECT is cold, it runs very nice with those settings. Before I zeroed out the table, it would hesitate / miss a bunch when cold. My wideband would go massively lean and the engine would feel like it died. Now, it runs perfect when cold.
I used to have to warm it up to 100*f before it would drive normal. Now I can drive it much colder if I have to. I normally like to warm it up though.

Screen shot - 2010 RA is the ATR table; 2010 GSR is the EcuFlash table (my car)
https://www.evolutionm.net/forums/at...1&d=1299005836

Yea I know how well it works, I have it zeroed on my Evo 8.

On the RA, if i zero it or even half it, I throw the P050B.

you guys might be talking about different tables.

there are two that are the same size and very close in values.

maybe post up your addresses to confirm :)

cold air is denser, which means there's more of it to use during the combustion cycle....principle #1 of turbos

The table I am talking about is at:

52680015 50793
555x000x 507a5

any updates on this? I suffer from excessive timing retard until coolant temp rises just a little bit... car falls flat on its face and goes lean, and I believe it is related (I knew there were more coolant related timing maps than met the eye)

Tephra, back to your original post question, warmup advance (adding), most aftermarket engine management have a 2D table to add timing when the coolant is low.
I believe it is to help with the slower burn rate of gasoline when cold.
Adding advance when cold certainly has hepled in these circumstances, so I was always curious as to why a corresponding table was not found in our ROMs.
Seems like it was there all along - will have to start searching again I guess.

there is a cold engine ign timing adder table. its been know and defined for a few years in several of the usdm roms.