Car Dying at idle during AutoMAF tuning sessions

[kwhiteside]

Hey guys, I've got a real show stopper now. During my last AutoMAF log run my car died 3 times putting in the clutch and coming to a stop. Sometimes the idle catches around 1500 rpm, then drops to 800 when I get close to not moving. Other times it just dive bombs down to 400rpm. When at 400, sometimes it bounces until setting on 800. But now its getting worse and instead of bouncing, it just dies.

Not good, and I don't think I'll do anymore runs like this till I address the dying situation.

Help greatly appreciated. I know JoeCar has a thread in his signature and I'll read that too.

Thanks in advance, Ken . . .

Last log and tune it was running on posted.

[kwhiteside]

I've done some research and it seems the right way would be to stop all my AutoMAF and AutoVE tuning and do the RAFIG process (more new learning :( )

But I found this post the makes some sense. Can I just pump up the spark below 800 rpm to keep it from dying like the quotes below?


You have to trick the car into using the timing to recover from rpm dips instead since the IAC won't do it for you. You can do this by making the timing at rpms below your idle (400, 600, maybe 800) higher than the timing at your idle rpm. This applies to the main and base spark tables.

For example, the stock main spark table has 19, 22, and 27 degrees of advance for 400, 600, and 800 rpm. So when you're rolling at 5 mph and the rpms dip, the lower the rpms get, the lower your timing gets. Change it to 35, 30, 25 and like magic no more dipping. Bonus: you shouldn't even need to change your idle airflow tables if you only change the timing at rpms below your idle speed.

[joecar]

Here's my sig (see "What to Tune Steps")... I don't have much experience with idle/RAFIG tuning.

[kwhiteside]

Read all of the below threads and must say some is totally over my head. That being said, I went ahead and tried to apply what I could gather as best guess with very little help other than the threads. With my tweaks in place, I died twice on the way to work this morning.


Idle Tuning:
showthread.php?t=4661 (this thread was way over my head and appears to be a lot of guesswork in areas I don't know if I need to go, very scary first read, especilly when he starts off referencing the RAFIG process which I cannot get working and nobody has chimed in as to why the IAC PID's are unavailable)

showthread.php?t=149
Another way overhead read, especially when he starts talking trims and mine are turned off for AutoMAF mode. Tried logging the IAC PID's and turning the trims back on, but i can't log the IAC PID's, so until I can log IAC, worthless thread to me.

showthread.php?t=5866
This thread made a lot of sense to me and I really want to perform this. Of course I can't get the RAFIG to log so I can't do it until somebody helps me figure that out. I do question how not driving the car can possibly rectify my problem though. My car idles fine most of the time. It's just when I'm rolling along and put in the clutch that it goes to zero rpm and dies. If I restart the car, it has always went back into normal idle. If I'm left without help for another day, I will take a guess at my B4307 values without going thru the process and see if it helps. The car is just about undrivable if it stalls out like it currently does. Very frustrating.

showthread.php?p=86553 post #17
Post 17 was another tread that made some sense to me. I went ahead and did everthing I could in this thread and took a chance driving the car to work with these tweaks in my tune.
b4603 desired idle 800 most the way, car does idle at 800 most of the time anyway. This table ok.
Spark Tables set the idle ranges to 22* and above, I did this and was hoping it would fix the problem. It did not. I raised a lot of 400rpm sparks from 16 to 22 degrees and smoothed in the 800rpm and 1200rpm ranges.
b4322 and other idle learn tables I set the high to 8 and min to -8 as described.
b4311 set to 10 was at 2
b3212 set to 9 was at 1

So post 17 tweaks applied I drove it to work and died twice on the way

Left on my own, and not being able to get RAFIG working due to the IAC PID's being unavailble in both the v8 BBL and the scan tool thru notebook, I would probably take a wild guess and bump the b4307 desired airflow 7.40 stock values up to 8.2.

Oh, and thru all my reading I found great irony in the one guy who got a magic mail order tune that solved his problems. Same tuner that solved his problems, had my car up on his dyno, sent me down the road with these divebomp rpm problems and told me I would be better off tuning it myself.

current tune and log with car dying twice attached

[joecar]

You're saying that the pids IAC_LTD_DMA and IAC_STD_DMA are not available for logging even after you validate pids (connect laptop to vehicle)...? I pm'd Tech Support.

Hmmm... I'm wondering if you should change OS from 12593358 to say 12212156...?
You would need a 12212156 file from a vehicle with ETC...
(you would have to copy all your tables, one-by-one, using copy-with-labels/paste-with-labels, a 2 hour process).

[bmax]

I had the same problem.
My OS 09373372, did not have the rafig pids supported. I changed to the 12212156 OS as Joe recommended and that helped a lot.

Good luck

Brad

[kwhiteside]

You're saying that the pids IAC_LTD_DMA and IAC_STD_DMA are not available for logging even after you validate pids (connect laptop to vehicle)...? I pm'd Tech Support.

Hmmm... I'm wondering if you should change OS from 12593358 to say 12212156...?
You would need a 12212156 file from a vehicle with ETC...
(you would have to copy all your tables, one-by-one, using copy-with-labels/paste-with-labels, a 2 hour process).

Yes, I just went out to my car to make sure I clicked the connect button and grabbed a screen shot to prove it. They are not available AC on or off, see screen.

Let me mention this. Since I started I had idle divebomb problems, but it never died or went below 500rpm. It was only after I made my Injector Flow Rate adjustments to lower the values in the table as shown in the pic that I started dying. Perhaps with that knowledge, there is a table I should have multiplied an adjustment to since my Fuel just changed across the board. see pic, I moved the values down, so I think the pcm had to squirt out more gas to achieve stoich. Perhaps I should be added some air somewhere at idle because of the more gas????

Now if I need to change OS, please give me some steps. I don't mind doing it if necessary, but there are a boatload of tables and parameters and I'm sure I haven't even looked at half of them yet

[kwhiteside]

Hey, if I can't do RAFIG due to my OS, what about this as an alternative. Apparently this has been a known problem with the software for 2 years that was supposed to be fixed according to the thread I found.

http://forum.efilive.com/showpost.ph...34&postcount=9
http://forum.efilive.com/showpost.ph...5&postcount=30

[joecar]

To change OS, do this:

- find a 12212156 file from a vehicle with ETC (required) and the same transmission (optional), make a copy if it, this is your new 12212156 file;

- if the 12212156 file is for auto trans car, you will need to find a 12212156 manual trans file, open this as alternate calibration and copy the transmission segment to the new file, save the new 12212156 file;

- close the tunetool and reopen it on your new 12212156 file;

- then another instance of the tunetool on your old 12593358 file;

- for each and every table do copy-with-labels from old file and paste-with-labels to new file (also copy the MT specific trans tables if they are different);

- you may find a few tables transposed, use the conversion table to un-transpose;
- you may find a few tables are not used in new, just ignore these;
- you may find a few new tables in new, try to find suitable values for these;

--> yes this is tedious, do it carefully, it takes about 2 hours;

- when finished, save the new file;

then do a full flash to your PCM (full flash takes about 2 minutes, so take all the usually precautions: accessories/headlights/drl/lights/radio off, OnStar disabled, etc...)...

then start the car, it should run pretty much identically on 12212156 as it did on 12593358...

12212156 has the advantage of allowing an easy upgrade to COS5 if you ever want/need to.