LNF Timing Tables with Idle Help

We have a VVT thread, Boost thread and others so i thought i would start one for people to post thier timing tables in to help others with milage, E85, or idle issuse that seem to be becoming more common. IF YOU USE THESE TABLES BE SURE TO LOG THE CAR FOR KR!! Every car is different and will take things differently.

If your having issues with a rough idle when turning on the AC or just plain idle read this. There are many major factors that go into getting a smooth idle. Timing, Airflow, cam timing, and fuel trims. Load also plays a huge roll. Your aiming for a 1.00 Lambda at idle. You need to have a smooth idle area in your tune as far as timing goes other wise timing will become erratic and give you a fluctuating load. In the scanner 0*-5* is normal as far as advance, when it goes beyond this you car hear the car surge or miss.
You basically want to start with your Maf correction table, Highlight the cells between 800-1000rpms and from 20% to 40% load. You can start with a average of those cells or just set them to 1.00. Next use the same idea on your timing table trying to correlate those same cells by adding or subtracting a couple degrees to make those cells as close as possible DONT PUT IN 1.0!!!. Be sure your cam timing area is stock aswell or set up for cat warm up disable. Next start the car, make sure its warmed up and STFTs have been recording for a minute or so then restart the logger "important other wise you will come up with a crazy STFT at idle". let the car idle for about 3-4minutes then turn on the AC and go for another 3-4 minutes. This will create a higher load and jump to different cells in all those tables you smoothed. Copy and paste special by % those cells into Maf correction. The fuel trims in the histo cells you use for no AC should be very close to the cells where you have the AC on. 20-30% load should be AC off and 30 to 40% load should be AC on. Repeat the logging process a couple times and check after each flash to be sure your two idle areas are not getting too far apart in value.
Quick way to do this if your car idles good with AC off but bad with AC on is to make the 20%load to 40%load idle area all the same in timing and Maf correction.
This whole problem should be avoided if you tune the car correctly but sometimes these few cells seem to stray out there with out people knowing.

Here is the timing table i use on my car to run full E85. I average 28-30mpg actual pen and paper tested. If you look at it you will see that I made a Hump for cruize just like the cam section. This may or may not be a good idea but my car loves it and shows NO random kr with this table. I have seen .7* a couple times coming off a light but its only on cylinder 4 "stg4 clutch chatter" It is also rolls timing in smooth when rolling into the throttle on a pull. Let me know what yall think about it, there is a funny story behind the idea to add the hump.

sounds familiar lol but my timing is alot lower then yours in the lower load but it idles smooth now!

Lower your idle timing more and it will be smoother still! I posted a tune in dayhoff's thread with my latest timing/cam tables, try those out :)

Im also going to re-write the guide and add all of the info about teh new tables in there soon :)

Sweet il look into that. I was hoping we could put all those tables that had to do with timing in one thread, just to get it a little more organized here.

Here's your goal guys...

http://i841.photobucket.com/albums/z...ll/hotidle.jpg

Here's cold start and idle. Dead solid throttle, ign timing and rpm. This is on E47, EFR turbo and blow through maf. (I've seen all these posts on colds starts being a problem with cat warmup off or with Ethanol blends. BS)...

http://i841.photobucket.com/albums/z...47EFRturbo.jpg

Here's a hot idle turning the A/C compressor on and off. I turned it on and off 3 times in this log screenshot. You can see where I turned it on by looking at the ign timing maintaining idle speed, but it's very hard to see when I turned it off. Throttle opening barely moves at all, which is ideal. Load goes from 14/15 to 16/17, barely any difference because the motor is capable of plenty of power to run the A/C at idle without big throttle and rpm variations...

http://i841.photobucket.com/albums/z...nonthenoff.jpg

When you guys are retarding the ign timing that far, yes it will get smoother, but that's only because the motor is under more load. (BTW, when you have the engine running RIGHT, you can't even feel it idle, and that's with NO balance shafts in the motor.) Notice my throttle angle and airload. (It's at 1 because this is a hot idle with no A/C, usually you'd want a little higher than 1.) NO motor wants tdc or close to it at idle, you need at least 5 or 10 degrees to get the motor unloaded at idle. That's why the difference between A/C on and off is so great, the motor is just having a hard time making enough power to run it. Bump that ign timing way up and you'll have a MUCH happier running motor, better mileage, and cooler running too. Never forget, ign timing is power. Even at idle.

Quote:

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Originally Posted by gmtech16450yz

When you guys are retarding the ign timing that far, yes it will get smoother, but that's only because the motor is under more load. Notice my throttle angle and airload. (It's at 1 because this is a hot idle with no A/C, usually you'd want a little higher than 1.) NO motor wants tdc or close to it at idle, you need at least 5 or 10 degrees to get the motor unloaded at idle. That's why the difference between A/C on and off is so great, the motor is just having a hard time making enough power to run it. Bump that ign timing way up and you'll have a MUCH happier running motor, better mileage, and cooler running too. Never forget, ign timing is power. Even at idle.

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This is what i thought! but im getting mixed idears here. I always wonderd why the timing advance at idle was so low. I dont see how your getting 19* though? Max i see is about 5* Im going to try bumping mine up slightly from what I posted earlier.

On my E tune i see -1 to 2* advance at idle at most.

Could this be the underlying cause for a rough idle when the engine is cold?? My car idles very rough when first starting it but gets smooth after it warms up. I logged a cold start to see what the timing was doing and it was very eratic.

Thanks
Ken

I retarded the timing around the 20-30% load zone and 600-1000RPM zone. I started the car cold and the idle was much worse. I turned it off immediately. I then went back into my timing tables and advanced it a few degrees in the same cells. Started the car and it seemed somewhat better. (I do have CAT-WARMUP disabled and it seems like it causes this problem from what gmtech said above) I advanced a little more but by then i couldnt tell if it was better because of the timing or because it was getting warmer.

NOTE: Im not getting ANY MAF Correction in the cells when logging the cold start, all 0's.
I have not changed the cam timing tables at all. I do not fully understand those tables yet.
I'm not getting any KR in that area and my LTFT are pretty good too.

If anyone can offer their help I would appreciate it.
Thanks
Ken

I forgot to say, when starting the car this morning, (cold) it surged and stuttered badly. So it doesn't seem like i got improved results for advancing or retarding my timing.

One thing you have to remember is that there is no closed loop fuel control on cold starts. You aren't going to see any maf corrections until it goes into closed loop. All the computer has to go by is what the fuel trims were when it was last shut off. If your LTFT's are -5, on a cold start it's going to be taking away 5% of the fuel no matter if it's actually rich or lean. It doesn't know whether it's rich or lean. If your LTFT's were at +5 when last shut off, it's going to be adding 5% of fuel on cold starts, again whether it needs it or not. There obviously are cold start fuel adders and modifiers, but we don't have control over those so I'm not going to get into explaining that.

On a side note, another thing to remember on this E69 Bosch ECM is that the LTFT's are a "global" setting. In other words, there are no LTFT cells, only one cell for every engine mode or condition. Most other ECM's have many LTFT cells, for many different situations referenced by tps, coolant temp, intake temps, rpm, etc, etc. You can have a rich LTFT compensation at idle, but off idle that LTFT compensation may be lean.
On the LNF, there is only one LTFT cell. That means if you're rich at freeway cruise and the LTFT's are at say -5, when you get to that stop light the LTFT will still be at -5. You may physically be very lean at idle, but the LTFT will still be taking away fuel unless you sit there long enough for the STFT's to push the LTFT's back towards zero. On any other ECM, you could be at -5 cruising down the freeway, but when you come to that stop and the engine is actually running lean, the LTFT's will have compensated for it separately already from the last stop so your LTFT's might be reading +5.

Make sense? Basically you need to make sure your fuel trims are as close to zero on LTFT's and STFT's for things like cold starts and idle to be smooth. If you get your maf calibrations and compensations close enough, you could easily run an LNF with the LTFT's disabled and have a perfect running motor in all conditions because STFT's wouldn't have to be maxed out in any direction at any time. (Hmmmm, how do I know that?)

okay that makes sense. I just got off work and am in the process of installing a K&N SRI. I'm going to go for a drive afterwords and try getting my fuel trims dialed in as close as possible. Ill post my tune and a log or two after and see what you think.

*BYT- I saw ur response in the other thread. I started with your tables a few weeks ago and have changed them just slightly.

Thank You for the suggestions, ill post back later.

This log was only about 10 min. It was all in the city and I was using the attached config (GMTECS). It wasn't reading boost and I didn't bother adding it so i just switched to my other config.
(I didn't make any changes based off this log)

I ran the first log and adjusted my LTFT's. (I also made a very minor adjustment on spark timing)

I logged my second log and the LT's stayed at zero most of the time. Afterwords I pasted the MAF Correction cells by 1/2.

Im going to do one more log and then upload that log along with my tune file so you can see the most current data.

Okay here's the last log i did. It was a pretty short log and I haven't changed anything on my tune file after running it.

*Sidenote, when going full throttle there seems to be a high Frequency Sound coming from the car, I'm not sure where from but it wasn't there a few days ago.(This may be the Intake i just put on??)
*My boost seems to build too fast. Like i give it 1/8 throttle to accelerate slightly and i get 5-7psi of boost almost instantly. I can also hear a flutter around 3k-4k RPM under hard accelerating. I never heard this before and think I may just be able to hear it now because of the intake letting more sound out.

Hey Kenny, I got your PM, just not sure if I can help you dude, sorry.

I have a ton of other stuff going on right now, I'm sitting here typing emails to guys trying to help them with their cars, typing on here trying to help and educate, and talking on the phone trying to help one of the vendors out. I'm questioning my sanity at this point because NONE of this is doing anything for me other than giving me some Karma points. It just takes a ton of time and I'm wondering why I'm spending all this time doing this instead of the 50 other things I could be doing. Not your fault or problem, I'm just venting!

So the one thing I can say is your logs are not friendly at all. That poor motor is running at about 60% of what it should be. There's a bunch of maf turbulence, ign timing is jacked, mixtures aren't right, VE airflow goes full scale at 5k (I've seen Vince's tunes do this, you don't have his tune in this do you?), your throttle mapping is sometimes too high, sometimes too low, etc, etc. Your dals are giving you too much throttle at around 2k rpms, but there's a ton of tm or something taking it and boost away at high rpm's and load. The throttle response and drivability can't be good on that thing.

Again, I'm not sure I can help you, and I'm not trying to slam your tune or your car, I know you're trying to learn and just starting out. I guess hopefully it will make you feel better knowing that your car absolutely CAN be running better than it is and if you get a decent tuner to help you hopefully it WILL run better.

Ill pm you really quick

Question... Do you guys find it better to make all of the 4 timing tables the same or to make similar changes to each of the tables when tuning?

Quote:

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Originally Posted by gmtech16450yz

you could easily run an LNF with the LTFT's disabled and have a perfect running motor in all conditions because STFT's wouldn't have to be maxed out in any direction at any time. (Hmmmm, how do I know that?)

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By unplugging the Evap purge solenoid. I run my car like this a lot actually. Makes it feel more responsive. I plug it back in every now and then on long cruizes or if im starting a different fuel mix to get a good idea on how far i need to scale.