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stalling and VE table question

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Old 05-26-2012, 07:47 PM
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Default stalling and VE table question

For the last week I've let VE Analyze Live work on my VE table. Now sometimes at idle, after driving, in hot weather, the car stalls. VEAL keeps wanting to jack the VE up sky-high in the low RPM/low MAP area. See attached image.

Thoughts? Suggestions?
Attached Thumbnails stalling and VE table question-veal.png   stalling and VE table question-afr.png   stalling and VE table question-graph.png  

Last edited by travisb; 05-27-2012 at 06:14 PM.
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Old 05-29-2012, 10:57 AM
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Upload the tune and a data log of it happening.
Use of proper injector dead times will help with this issue as well.
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Old 05-29-2012, 11:05 AM
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lol at your VE table at idle.

the issue is your AIT-density based corrections, or lack there of. Adjusting the dead times will not solve the issue of the ideal gas law code pulling a lot of fuel when the AITs get hotter than 80°F causing really lean idle and overcompensating with that horrible fuel map.
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Old 05-29-2012, 11:09 AM
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tune and datalog is needed to make sure of the issue, I'm pretty sure its the ideal gas law issuel.
But it will help out on issues regarding the fuel injection being more steady at varying loads\temps\etc
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Old 05-29-2012, 11:13 AM
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Thanks.
I attached the tune and log from Saturday when it cut out several times.
I also attached the tune and log from this morning. I had to trim the log to upload. The revs dipped some this morning, but it did not cut off. It wasn't too hot out yet.
Attached Files
File Type: msq
2012-05-29_10.58.45.msq (40.3 KB, 156 views)
File Type: msl
2012-05-26_16.19.34.msl (1.92 MB, 150 views)
File Type: msq
2012-05-26_16.54.31.msq (40.3 KB, 127 views)
File Type: msl
2012-05-29_07.31.25 - Copy.msl (1.44 MB, 113 views)
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Old 05-29-2012, 11:17 AM
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gair is all over the place, where is your IAT sensor at?
Also not sure how ms1 works in their corrections but I'd look at turning the gair effect on fueling down if possible.
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Old 05-29-2012, 11:18 AM
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yeah, look at your Gair log on 2012-05-26_16.19.34.msl, in places it's hitting 142%....so you're adding 42% more fuel at a given air temperature.

and you're tuning against this causing you to have horriblly awful VE% numbers in your table.

you need to tune the clt-based air density table curve in such a manner that you negate any code trying to add/subtract fuel. I can't remember what the table value that work for msI are, I'd have to look for them. But your current table is WAYYYYYYYYYYYY too agressive and causing you to dump in and acutally pull out too much at a given air temp. So turn on the Gair gauge on your virtual dash and start manipulating the curve so it stays at 100% all of the time.


youre going to to have to retune your fuel map afterwards. I'd acutally move your first 4 table values back to the 35VE% area to match the rest of your table and go from there.
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Old 05-29-2012, 11:36 AM
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Thanks. See attached image. Is this the table you're referring too? How should it be set?

The IAT after the IC, behind the radiator.
Attached Thumbnails stalling and VE table question-clt_correct_air_density.png  
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Old 05-29-2012, 11:40 AM
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yes. and i told you how to set it.


behind the radiator lends the ait to get heat soaked once the car is off and at idle.
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Old 05-30-2012, 07:22 PM
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I've been studying this topic some more, but where is the gair gauge so I can watch the values in real time?
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Old 05-30-2012, 10:25 PM
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Right click any gauge on the dahsboard to change it
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Old 05-30-2012, 10:44 PM
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Yes, I tried that. I did not see anything similar to "gair".
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Old 05-31-2012, 10:28 AM
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Attached is a screenshot showing the available gauges that I see...
Attached Thumbnails stalling and VE table question-gauges.jpg  
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Old 05-31-2012, 10:34 AM
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oh msI. use the gammae gauge. it includes ALL enrichments, so you'll have to wait until ASE and warmup are over.
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Old 05-31-2012, 04:09 PM
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Ok, I added the Gamma Enrichment gauge and tuned the Coolant Related Air Density so that the G E was around 100%. I couldn't do the whole table because it is already 85 degrees out.

Attached is a screenshot of my Coolant table and the gauge too, just in case any other MS1 users want to see the gauge.

When it was at 100% I let VEAL take over and update VE and my AFR started coming into a better range.

Does my coolant table look like I'm doing the right thing??? What kind of temperature range should I cover? It seems better...
Attached Thumbnails stalling and VE table question-gamma_enrichment.png   stalling and VE table question-coolant.jpg  
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Old 05-31-2012, 04:38 PM
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your table is going backwards. correction should be at 100% around 80°F intake temps, and till need to increase as the AITs increase.
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Old 06-01-2012, 08:21 AM
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Thanks, I've updated my table. See attached. Is 80-140 degrees an appropriate target for this table?

I have another question. I have it set to start reducing correction at 2000rpm and end correction at 3000.

This morning when I was on the highway at 3500-4000 rpm the GAir was at 96% or so. Since correction should have already stopped, do I need to worry about trying to get that to 100? Would that be through adjusting the VE table to narrow it in?
Attached Thumbnails stalling and VE table question-coolant2.png  
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Old 06-05-2012, 07:59 AM
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Thanks Brain. I have Gair somewhat under control. It was between 98-101% this morning commute. The VE table is starting to smooth out and AFR is getting much more steady.

Can you take a look at the attached picture? It is a scatter graph from this morning showing AFR vs MAP vs Gair.

I have a few (dark blue) dots above 100MAP and 14 AFR. Do I need to worry about those few?

Also, under low MAP, usually while decelerating I hit very high AFR. 21.7 or whatever the max on the scale is. Is that a concern? I do have over run at >2k rpm, <20kpa.
Attached Thumbnails stalling and VE table question-scatter.png  
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Old 06-05-2012, 08:04 AM
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Originally Posted by Braineack
lol at your VE table at idle.

the issue is your AIT-density based corrections, or lack there of. Adjusting the dead times will not solve the issue of the ideal gas law code pulling a lot of fuel when the AITs get hotter than 80°F causing really lean idle and overcompensating with that horrible fuel map.
+1, I'm saving this ----.

good job getting your stuff fixed.
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Old 06-05-2012, 08:10 AM
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Originally Posted by travisb
Also, under low MAP, usually while decelerating I hit very high AFR. 21.7 or whatever the max on the scale is. Is that a concern? I do have over run at >2k rpm, <20kpa.
Show us the log.
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