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View Full Version : Problems with idle after AutoVE flash (again)



mtnman
June 8th, 2006, 12:00 AM
I've already got an SD Tune which was developed from following the AutoVE tuning tutorial. The LTFTs fell within the -4 to +4 range, so I was going to go through the tuning tutorial again using the current SD tune as a starter. I followed the tutorial, modifying the settings in the current SD tune, then flashed the tun into the truck. The truck wouldn't stay at idle even when giving it gas. There was the strong smell of gas, so I increased the initial B0101 table by 5% over instead of the recommended 15%, flashed the tune, same problem, truck wouldnt stay idled after cranking and there was the strong smell of gas again. I'm wondering, does this tuning tutorial have to start with a "stock" tune as opposed to a tune which has already been through the VE tuning process? I've gone over the settings about 5 times and everything seems to be set correctly in the SDAutoTune.tun file. I cant figure out why this is happening again. I went through all my notes for other values to modify in the tune and made those changes (increase C6101 by 100%, set C2903, C2904 and C2906 to zero,zero out B5001), but truck still wont idle. Have I left out a modification?

SSpdDmon
June 8th, 2006, 02:42 AM
When doing a SD tune for the first time, it is suggested that you increase the VE as a safety precaution. If you're working from an existing SD-tuned VE table after minor or no mods were made, then you don't have to do this. C6101 only needs to be increased 100% once as well. The tutorial is designed to help get you into SD mode safely the first time.

After the first time, all you need to do is kill the MAF (high freq. fail to 0 & high freq. fail limit to 1) and copy the high ocatne spark table to the low octane table. If you want to turn the SES light off after killing the MAF, you can...but you don't have to. You can turn off DFCO, but you don't have to. I prefer to leave it on and filter it out of my logged data.

At this point you're in CLSD (closed loop speed density), which means you still have LTFT's and STFT's trying to keep you at 14.63 unless PE kicks in. When tuning with a wideband, you need to get rid of these things. I prefer to leave PE enabled and set it to a single figure (like 12.2AFR across the board). Then in the Commanded Fuel In Open Loop table, command stoich (14.63) for all cells at all ECTs greater than 170* & less than 230*. To get rid of LTFT's, you disable them with {B3801}. STFT's are disabled by setting {B4205} Closed Loop Temp Enable to 256*.

Now, you're in OLSD (open loop speed density) and are ready to log (once your vehicle has been at operating temps for a few minutes). Proceed with the AutoVE tuning.

Once finished, re-enable the MAF settings (fail frequencies) and restore the low octane spark table. This will move you from OLSD to plain OL. You now need to tune the MAF. If you haven't already tuned the MAF, it's a good idea to increase the MAF table slightly (just like you did the first time with the VE table) as a safety precaution. Log your commanded AFR vs your WBO2 AFR for each MAF Frequency. The correction that needs to be made for each frequency is (WBO2_AFR/Comm_AFR). If you command 12.0 and read 13.0, you're lean - which means you need to increase the MAF table by 13/12 or 8.3% for that frequency. To dial it in closer, you can apply only half of the correction (4.2%) to avoid overshoot.

Once the MAF is done, restore the stock closed loop temp enable & commanded fuel in open loop tables, enable LTFTs, and set your PE where you want it. I think that's all there is to it. Enjoy! :)

vetteboy2k
June 8th, 2006, 08:35 AM
SSPDemon,

What do you add to filter out dfco cells? Use the current BEN Filter for throttle position / coolant temp and Add To Exclude Fuel Trim Cells Greater than 19?

mtnman
June 8th, 2006, 09:31 AM
SSpdDmn,

I think you misunderstood my question. I have successfully completed the Auto VE tutorial once. I followed the directions 2nd time around, starting with the Closed loop SD tune from the resulting previous Auto VE tune. My problem is that the truck cranks for about 3 seconds then shakes and cuts off, but there's the strong smell of gas. I've tried tunes with B0101 set at the original values, at 5%, at 8% and at 15%. The truck will not idle off a start with any of the VE table settings. It's worked once starting with a fairly stock Tune file, but now after starting with the SD tune, I cant even get the truck to stay idled after cranking it. I'm thinking there is some value that I've left out which needs to be modified. I cant find this value in my notes.

purrvert
June 8th, 2006, 09:45 AM
Take a look at some of your tables, B3604 comes to mind to see if the numbers match the units. I've had 16 EQ in the forementioned table.

SSpdDmon
June 8th, 2006, 12:32 PM
SSPDemon,

What do you add to filter out dfco cells? Use the current BEN Filter for throttle position / coolant temp and Add To Exclude Fuel Trim Cells Greater than 19?
yup...

SSpdDmon
June 8th, 2006, 12:35 PM
Take a look at some of your tables, B3604 comes to mind to see if the numbers match the units. I've had 16 EQ in the forementioned table.
Ditto. 16.0 AFR vs an EQ of 16 are two very different things. Any chance you missed something like this?

Incase you did, you could try loading the stock table as a comparison and going over each table to make sure the changes made are ones you really wanted to make.

98SS2836
June 9th, 2006, 12:16 AM
im having the same problems went through the tutorial tried to start the car died again died held the throttle all the way down got it started but it was comanding 1.1:1 AF so it would just die. Dont know yet trying to figure it out Put my original file back in car starts fine?

joecar
June 9th, 2006, 02:35 AM
As SSpdDmon said, watch your units, are you using AFR, EQ or Lambda...?

Sounds alot like your units are EQ and you're setting the values as AFR, or vice-versa.

98SS2836
June 9th, 2006, 08:29 AM
I must have had my units messed up I wanted to use all AFR. I just started over and now its seems to be fine.

mtnman i would just start over and leave it in EQ

joecar
June 9th, 2006, 08:36 AM
I use EQ throughout, makes it mentally easier for me (% rich or % lean).

98SS2836
June 9th, 2006, 08:54 AM
car still wont idle running pig rich Im just trying to Auto VE tune it Comanding 14.63 and running at 9.5-10 If i keep on the gas will stay running off wont I have 30lbs and a ractronix pump ?

mtnman
June 12th, 2006, 09:58 AM
Looks like it did turn out to be the P0101,P0102, and P0103 settings. I had forgotten that they're on multiple tables , E0102 and E0104.

jamesbond2509
October 4th, 2006, 02:17 PM
Looks like it did turn out to be the P0101,P0102, and P0103 settings. I had forgotten that they're on multiple tables , E0102 and E0104.

Can you clarify as I think I am having the same problem E0102 is a transmission setting?