Fueling table viable year round?

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Fueling table viable year round?

Postby 88a5tq » Sun Jan 22, 2017 12:19 pm

I had to retune my fuel table in the dead of winter (technically still winter lol) but when we filmed my vid yesterday the log showed it was running pretty rich whereas all was great during the previously much colder week. What other table am I supposed to modify to help make the fuel VE table be viable all year? Please and thank you :)
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Re: Fueling table viable year round?

Postby 88a5tq » Sun Jan 22, 2017 12:52 pm

I was using the MAT/TPS fuel enrichment table but reverted to 100 after not liking the results. Anyone think I was right the first time haha? Anyone willing to share theirs?

My brain tells me decrease fuel on the right below 100 depending on what temp the fuel table was working for. For me it was 11 C so I guess I'd leave fueling the same and just subtract from 100 accordingly until it's fine and good. Am I an idiot?
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Re: Fueling table viable year round?

Postby loxxrider » Mon Jan 23, 2017 1:06 am

That's the right table to be messing with. Unless your coolant temps are noticeably hotter now. In that case, check out the warmup enrichment curve.

As far as how to tune it, just see what cells the car is operating in at the temperatures which are causing you problems. Adjust that cell and the ones immediately around it to something that works and then scale the rest of the table linearly. That'll get your started anyway. Then you can go test the tune and tweak a little more if necessary.
-Chris

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Re: Fueling table viable year round?

Postby 88a5tq » Mon Jan 23, 2017 12:14 pm

Thanks dude! You see the vid in my build thread? ;)
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Re: Fueling table viable year round?

Postby loxxrider » Tue Jan 24, 2017 7:35 am

Yes and I love it
-Chris

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Re: Fueling table viable year round?

Postby UrSobsessed » Thu Feb 02, 2017 8:20 pm

When I started using the MAT/TPS table, I tuned the VE table when the intake temps were 20C +/- 2C. Then I used the 20C column in the MAT/TPS table as my baseline or 100%. Then I went up and down from there. What I noticed is that it didn't take much at all of a percentage change to make a difference. The default values in that table were way too extreme for my set up. I think I ended up having a total swing of about 102%-98%. It's been a while since I have messed with that table but I do remember having some success with this method.

HTH
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Re: Fueling table viable year round?

Postby 88a5tq » Thu Feb 02, 2017 8:32 pm

Sounds good! I also have a swing of 102 to 98 and it seems to be better. Thanks
Last edited by 88a5tq on Fri Feb 03, 2017 7:23 am, edited 1 time in total.
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Re: Fueling table viable year round?

Postby ChrisAudi80 » Fri Feb 03, 2017 4:34 am

UrSobsessed wrote:When I started using the MAT/TPS table, I tuned the VE table when the intake temps were 20C +/- 2C. Then I used the 20C column in the MAT/TPS table as my baseline or 100%. Then I went up and down from there. What I noticed is that it didn't take much at all of a percentage change to make a difference. The default values in that table were way too extreme for my set up. I think I ended up having a total swing of about 102%-98%. It's been a while since I have messed with that table but I do remember having some success with this method.

HTH

Could you post a picture of your table? TIA.
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Re: Fueling table viable year round?

Postby UrSobsessed » Sat Feb 11, 2017 8:48 pm

I will when I get home.
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Re: Fueling table viable year round?

Postby UrSobsessed » Sat Feb 11, 2017 11:30 pm

Here is what I'm running. There's a bit more swing in the table than previously mentioned. It's been a while since I've looked at that table. My car is in limbo waiting for an oil comsumption issue to be resolved so I don't drive it much at all. :/ Anyway, the -40°, +80° and 100° cells are guessing at a slope. I don't know if those are correct because I have not seen those intake temps in my car while tuning yet. Yeah. I've only been driving it in moderate ambient temps. The 106% at -20° is too high though. I'll likely set that at 104%. HTH

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Re: Fueling table viable year round?

Postby ChrisAudi80 » Sun Feb 12, 2017 9:11 pm

Thank you. I will study this more later. Thing is, I will never see the lower temp parts of that table. Lowest ambient temp I have ever experienced here is 11c.
Normally, anywhere from lowest 15c to highest 42c ambient. IATs anywhere from 25c to 55c. Lately with ambient 25c I see 48-50c IATs cruising in traffic. Seems kind of high.
I am starting to think my IAT sensor is going out or my 1.8t AEB IAT sensor resistance look-up table is off. I had to adjust the CLT curve.

If anyone would care to show the correct look-up table for the 1.8t IAT sensor, I would really appreciate it.
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Re: Fueling table viable year round?

Postby UrSobsessed » Wed Feb 15, 2017 3:14 am

48-50 IAT doesn't sound high to me for 25c ambient if you're in traffic, especially stop and go. Others may disagree, but my temps go up driving around in the city during the summer. When cruising, they go down to 20-30c. I've been using the supplied curve with the firmware for the 1.8t sensor.
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Re: Fueling table viable year round?

Postby ChrisAudi80 » Thu Feb 16, 2017 12:02 am

UrSobsessed wrote:48-50 IAT doesn't sound high to me for 25c ambient if you're in traffic, especially stop and go. Others may disagree, but my temps go up driving around in the city during the summer. When cruising, they go down to 20-30c. I've been using the supplied curve with the firmware for the 1.8t sensor.

Yeah, its not too bad. If I start with an IAT of 40c and go from 100kpa to 200kpa for 10seconds, IAT goes up to 47c.
I have been adjusting the MAT/TPS table the last few days. Can't believe I ignored this for so long :bangshead:
Always expected my EGO correction to take care of things. Silly me. Every time after a run, I am adjusting my VE table up and down in the same cells. Drives me up the wall.
Still, I have been fine tuning my warm up enrichment, now the MAT/TPS fueling. I was reading some posts on the Guild of EFI FB page yesterday and realized that of course IAT has an influence. I am an idiot :shame: 3% air density change per 10c change.

I am using 40c now as my benchmark, because that is my usual IAT when engine is warm. Put my MAT/TPS table on a linear slope. Just watched my hot idle IAT sitting at 52c and 1.04lambda, inj PW was 1.6ms, which is the lowest stable PW for 630cc Dekas. Adjusted the table and went right back to 1.0. Win. Learning by doing takes a long time...

Awesome quote from a dude of the fb page: "Scotland, we have really dense air." :lol:
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Re: Fueling table viable year round?

Postby UrSobsessed » Fri Feb 17, 2017 12:39 am

Cool! I'm glad this is helping.
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Re: Fueling table viable year round?

Postby ChrisAudi80 » Fri Feb 17, 2017 2:45 am

UrSobsessed wrote:Cool! I'm glad this is helping.

:beer:
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Re: Fueling table viable year round?

Postby 88a5tq » Tue Feb 21, 2017 9:06 am

Just caught up on this thread. I'm glad we are all sharing :)

My table is looking odd lately. I will post it after work. I think my 7a can set has something to do with it as well as my straight pipe exhaust.
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Re: Fueling table viable year round?

Postby ChrisAudi80 » Wed Feb 22, 2017 4:34 am

88a5tq wrote:Just caught up on this thread. I'm glad we are all sharing :)

My table is looking odd lately. I will post it after work. I think my 7a can set has something to do with it as well as my straight pipe exhaust.


Which table? MAT/TPS or VE?
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Re: Fueling table viable year round?

Postby 88a5tq » Sun Feb 26, 2017 5:05 pm

Sorry I mean MAT/TPS
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Re: Fueling table viable year round?

Postby ChrisAudi80 » Sun Feb 26, 2017 9:50 pm

That IS an odd table. How did you come up with this?
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Re: Fueling table viable year round?

Postby 88a5tq » Sun Feb 26, 2017 10:02 pm

I've only been in the middle 4 column range
You can probably disregard all but those and the -10 one I think. Just the nature of the beast I guess lol
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