I am still struggling trying to figure out the warm up tune. I thought I was making things better by increasing the % bins in the enrichment table, but got to a point where it ran worse, and it still wants to die when first started. So here are the questions:

1. How does changing the Afterstart enrighment effect things? Current setting is 21.

2. How does changing the number of engine cycles, right below that cell effect things? Current setting is 254.

3. How does changing cold Accel Multiplier effect things? Current setting is .07

4. How does changing the cold Accel Enrichment effect things, and what are the differences between number 3 and number 4 here? Current setting is 135 for cold accel multiplier.

The main thing is trying to figure out the differences between these fellows so I can interpret the effect of changes as I make them. I would like to be able to drive the Dart in cold weather, but so far have felt the drivability issues were too severe. I work only 4 miles from home, and it just starts running well by the time I get to work when the weather gets cool and then cold.

Anybody worked out a strategy for this? YOU guys in Southern California probably don't have to deal with this issue. Poor guys.

Sam

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It increases fuel in the first brief time period right after starting. Larger numbers add more fuel. This is applied on top of all other enrichments, including warm up enrichment, as well as the main fuel table. So all the other settings need to be spot on before setting final values here.

It also sounds like you may be running an older code variant, as newer ones allow different values at different temperatures. Generally this needs to be more as temperature gets colder.
This is how long the afterstart enrichment is applied. Each cycle is two revolutions of the crank. Instead of time, it goes by how many engine rotations since startup to determine how long to apply afterstart enrichment. (Later firmware versions let you switch between time and cycles.)
These numbers take effect when you give the throttle a quick stab but are not in effect at idle (or at least they shouldn't be. The top number is how long the cold acceleration pulse lasts and the lower number is how much to increase the amount of fuel added. This is applied on top of normal acceleration enrichment.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

Thanks for the input there Matt. When you start it cold, it actually will idle although poorly until you you touch the throttle, and then it dies. So numbers 3 and 4 are pretty certain in need of increasing.

Is this "older code variant" something that can be upgraded in this ECU or is that embedded in the hardware somehow? I can see the need to have these figures different for different ECT in the warm up. Is this another reason to upgrade to MS II?

Thanks, Sam

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You can load the processor with the newest MS1/Extra firmware (what used to be called MSnS-E) without any hardware changes and get the advantages I talked about. The bad news is you can't load the current tune. The VE and spark tables can be exported; the rest has to be copied over by hand.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

Thanks Matt, Your info on the warm up table was a big help. I raised the values for the warm up accel values and it helped big time. I raised it until it did not want to die when I touched the throttle. That is a huge improvement. Thanks again. Later on I will research the process for downloading the new firmware. I still may simply upgrade to MSII some time soon.

Sam

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Sam,

Are you using Megatune 2.25? What version? That is the latest for MSI, I believe. Glad you are making progress. I encourage you to read Megamanual for the particular meanings of those settings. I have found that the required enrichment values for low temps were almost all much more than I expected.

Lou

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Home of Slant6-powered fun machines since 1988

Read? I thought that was no longer needed in the video age. Oh yeah, there is texting. LOL! That's going to keep reading alive and well. Aren't books going to eventually be obsolete? OMG!

Sam

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According to our undergraduates, books are already obsolete. We haven't figured that out yet... I guess they know everything.

Lou

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Home of Slant6-powered fun machines since 1988

I guess I'm young for my age in more ways than just my youthful appearance.

Sam

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Keep in mind that the same MegaTune version will display different features depending on the code version he's using. But 2.25 is the latest MegaTune.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

Matt, can you explain to the resident electronic (and computer) dunce,(me) how to upgrade the internal code to get the new features embedded in the MS I? If I understand you correctly, the later version has different after-start enrichment coefficients, and maybe accel coefficients for different ECT's. I can see the need for this clearly. This would allow you to tailor these things more closely to the real needs of the engine at any given ECT. What other features does the later code carry with it?

But as you can see, I don;t even have the correct vocabulary here to get started. I don't know the correct terms to use, much less how to go about getting the down load performed. I am not at all afraid of the manual re-entry of basic configuration values in the tables. That seems pretty straight forward, and doable to me.

If you think this would be too tedious to post in this thread can you at least point me towards on line instructions for me to follow. I do have a computer savvy daughter who could help me. My problems usually start with the very first dialogue box that opens and asks me question where I am not sure if the incorrect selection is going to make my computer explode. At this point I typically give up and go watch a football game, or cut the grass. Thanks, I know I have asked a lot here. I always feel very grateful for help put out here.

One of the reasons I took on this EFI project was to keep my head in the modern world so to speak. Before my father-in-law (who lived with us for his last 4 years) passed away, he could do nothing for himself in our house. He could not use a microwave, telephone or the TV because he did not understand the modern controls. Fortunately the bathroom facilities had not changed appearance or function much from his childhood.

So, I am eager to stay involved with the computer end of the EFI, and to keep learning. The fact that I can now post a photo on the forum is evidence that to some small extend I am making progress. Thanks again.

SAm

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