Need a little help

[DaddySS]

After re-doing my 00 to 02 OS conversion, I have nearly all the issues sorted out with the a/c over correction, 02 codes, etc., etc.. A few remaining issues that are going to take some time but one that has me stumped.

At certain times, when coming to stop, I depress the clutch and get a near stall condition. It doesn't happen when stopped or when the throttle is depressed.

It looks like I depress the clutch which deactivates the throttle cracker the but since the car is moving the other corrections aren't activating?

I have attached the log where you can see at frame 380 I depress the clutch, and at 387 the idle has dropped to 450 then recovers (can't see why it recovers either).

Only things I can think of:
Add throttle follower in park/neutral?
Direct airflow correction P/N
Spark airflow speed control delay?
Idle learning temperature?
Spark overspeed correction?


Any help much appreciated.

[DaddySS]

Absent any input, I think I have two problems, the base spark in gear and p/n are too low and the spark underspeed and overspeed need to be adjusted. I had used the 02 tables to correct the flare on start up but I think they are too aggressive for the other conditions as sspdmn points out in his idle tutorial, will try that today.

[DaddySS]

OK I give up on this one. Cannot stop the near stall and tried a great number of changes. Once it's warmed up it's fine but before 170* or so it drops to near stall when rolling to a stop and clutch depressed.:mad:

[Goldfinger911]

Does this happen when depressing the clutch at a lower speed, like in a parking lot, only? Or while rolling at high speeds too? I have the same problem but only when driving around say a parking lot, or backing out of my driveway. I have a 2002 TA. I have been battling this for 2 weeks. :(

One thing that did "seem" to help, was I copied the stock values for the Throttle Follower Decay and Delay back in. Mine were altered, causing decay to happen faster. (larger amount decayed rather).

[Goldfinger911]

I just looked at your log. Now, I am no expert but I notice that your Throttle Follower airflow goes to zero immediately the instant your throttle position goes to 0%. I have logged mine recently, and I am pretty sure the follower "lags" behind the throttle position. So, your throttle closes, then a few seconds later, the TF Airflow decays to zero. The way I understand it, that is how it is supposed to function to avoid the behavior youre describing. Is someone wants to chime in and tell me I am smoking crack, please do. :)

[DaddySS]

I have it more agressive because the idle has hanging for several seconds when I came to a stop and deceleration was really slow. The odd thing is that it is only happens half way between cold and warmed up engine, and when I originally did my 2002 OS conversion it didn't have this problem.

[lastcall190]

Bump... you ever get this straightened out? I just developed the same problem switching from 00 to 02 system as well. Thanks.

-J

[SSpdDmon]

Load a copy of your tune with a list of mods and I'll take a look tonight if I get a minute. :)

[lastcall190]

Thanks here you go.

-J

[SSpdDmon]

mods?

[lastcall190]

Ooops sorry.

LS6 intake, LTs, TSP TDs, SLP lid, 224/226 .609/.585 111+2 cam, Extreme Gold Springs... am I missing anything very important? Thank you.

-J

[SSpdDmon]

Ooops sorry.

LS6 intake, LTs, TSP TDs, SLP lid, 224/226 .609/.585 111+2 cam, Extreme Gold Springs... am I missing anything very important? Thank you.

-J

I'm assuming M6 since you have 3.42s?

[lastcall190]

Again... yes, sorry.

Not trying to be a smart ass but I just keep forgetting it, perhaps I'll finally get you all the info you need by the next lunar cycle.

[SSpdDmon]

Again... yes, sorry.

Not trying to be a smart ass but I just keep forgetting it, perhaps I'll finally get you all the info you need by the next lunar cycle.
Cats, AIR, EGR? http://www.motownmuscle.com/forums/images/smilies/lol.gif

[lastcall190]

Oh man :bash:

No cats, no EGR, no AIR (EGR and AIR have been bypassed and blocked off, headers are NOT race headers). Slow day at work today, if there's anything else just post and I'll give out more info. I am throwing 5 codes but guess what, I don't remember what codes they are, I took my beater to work today :lol:

-J

EDIT: for what it's worth, the codes were NOT there before the switch of OS. Maybe it was just a coincidence that they came up, maybe not. 4 of the 5 were related to 02 sensors, that's what I do know. One was related to the AIR system valve 2 or something or other. HTH.

[SSpdDmon]

Oh man :bash:

No cats, no EGR, no AIR (EGR and AIR have been bypassed and blocked off, headers are NOT race headers). Slow day at work today, if there's anything else just post and I'll give out more info. I am throwing 5 codes but guess what, I don't remember what codes they are, I took my beater to work today :lol:

-J

EDIT: for what it's worth, the codes were NOT there before the switch of OS. Maybe it was just a coincidence that they came up, maybe not. 4 of the 5 were related to 02 sensors, that's what I do know. One was related to the AIR system valve 2 or something or other. HTH.
OK....I didn't really mess with fueling. But, I went through and re-worked everything else pretty much.

1) It looked like you didn't have all of the tables copied over correctly when you switch OS's. It almost looked like you used an automatic file. So, attached is a clean copy of a 2000-OS>2002-OS stock M6 file.

2) I'd highly suggest opening these and typing in your correct VIN# in both files uploaded as they seem to just have a generic one.

3) Try my tune out. When you load it (after you have typed in your VIN), use a full flash to make sure everything in the background is working right too.

4) Keep an eye out for KR. Your timing looked a little low at WOT and a little high at part throttle. The new timing adjustments should feel a little better as well as eliminate any surging you may have had. Changes to the throttle cracker/follower should help with that as well. Regardless, if you see KR consistently in some areas, you may need to pull some timing.

5) Like I said earlier, I didn't touch fueling other than the PE Enable table, which I made more aggressive. It appears whoever tuned the AFR took a similar approach to a MAF translator seeing as though all fueling corrections are made to the MAF curve. Cleaning up the fueling tables (MAF, VE, etc.) by tuning them to be more accurate may help with significantly with your idle.

6) Also, look into the RAFIG process. It didn't appear to be done with your tune. Granted the cam isn't that large, it can still help with idle consistency throughout the normal ECT range.

7) LMK how everything is. :D

[lastcall190]

Thank you very much, I will check it out this weekend. PM sent.

-J

[DaddySS]

For what it's worth, I have yet to solve the problem. It is dependant on how long the engine has been running. Sometimes it does it just a little, sometimes it either near stalls or stalls. I have it mostly contained it by adding timing in the 400 and 600 RPM range in the main and base spark tables.

[DaddySS]

In trying to disect this problem, I am tracking where the timing is coming from. Throttle is closed, vehicle speed is within the base timing enable threshhold but above the idle correction threshhold (0mph) so it should be using B5932 Base Spark in gear. As a for instance, when it goes from 2mph to 1mph (clutch is depressed) the timing changes (from the log) but engine speed and dyn. cyl. air. haven't changed.
Question; Shouldn't it go from Spark High Octane table to Base spark table when the throttle is closed and then enter idle correction at 0 mph without any other correction at like 2mph or 1 mph? Is there a parameter or a threshold that I am missing?

[SSpdDmon]

In trying to disect this problem, I am tracking where the timing is coming from. Throttle is closed, vehicle speed is within the base timing enable threshhold but above the idle correction threshhold (0mph) so it should be using B5932 Base Spark in gear. As a for instance, when it goes from 2mph to 1mph (clutch is depressed) the timing changes (from the log) but engine speed and dyn. cyl. air. haven't changed.
Question; Shouldn't it go from Spark High Octane table to Base spark table when the throttle is closed and then enter idle correction at 0 mph without any other correction at like 2mph or 1 mph? Is there a parameter or a threshold that I am missing?
Look at the tunes I posted above (http://forum.efilive.com/showpost.php?p=59201&postcount=16). Aside from the fueling, the spark tables, idle tables, etc. should all work for you. Load both in at the same time to see the differences. Then, try 'em out on your tune. Same goes for you too....keep an eye out for KR. :)

[DaddySS]

Thanks, as always I appreciate the response.

I made good progress today from the following respect:

I had been tracking the RPMs, timing tables etc. via the data from the logs but could not reconcile what the log said versus the table. In other words, log says at 2 mph, 0 throttle, 800 rpm and .40 grams per cyl I should be commanding 22* but the log showed 14. If I look across the table to 14* the grams per cylinder should be .48. I checked it against all of the areas where my idle was dying and found the same pattern.

I added spark in those areas of the main and base tables, specifically in the 600, 400 and 0 rpm ranges and my initial couple of drives show very good results.

In the meantime, I am comparing and looking at the tunes you sent and I appreciate the insight.

[lastcall190]

Thanks for the help SSpdDmon

[SSpdDmon]

Wow, it was off by that much? Do u have the log? Is it idling any better?

[DaddySS]

Looking at the tune you sent:
B3318 DFCO RPM - why 400 lower - is there a specific target for this change?

B0107 Max speed for idle - changed from 0 to 3kmh. This is an important one for all the "near stallers" out there, and I thought about it for mine but wasn't sure about the effect it would have in other areas like bucking at low speed, initial take off etc. What effects have you seen if any?

B4503 Filtered airflow - .5 shorter, why?

B4505 Direct airflow control from 1.8 to .3 - is that to stop it from going too far before you begin correcting?

B4309 Throttle cracker - very different from the 2000 table - what was the reasoning behind this approach and what results has it had on low speed roll, and other driving characteristics?

B4311 Throttle Cracker activate - is the higher speeed to keep it out of the light throttle slow spped roll area?

B4305 Throttle follower - reduced airflow but increased RPM multiplier - what were your thoughts behind that approach?

B5917 Base spark enable - whay change from 69kmh to 410?

B5920 Spark smoothing - what does it do?

I haven't had the courage to try the full tune yet but if and when I do I assume I plug in my VE (mostly), my timing "strategy" (I'm lower in the open throttle areas due to the 11 to 1 compression and 8.8 DCR), And my MAF calibrations?

[SSpdDmon]

Looking at the tune you sent:
B3318 DFCO RPM - why 400 lower - is there a specific target for this change?

B0107 Max speed for idle - changed from 0 to 3kmh. This is an important one for all the "near stallers" out there, and I thought about it for mine but wasn't sure about the effect it would have in other areas like bucking at low speed, initial take off etc. What effects have you seen if any?

B4503 Filtered airflow - .5 shorter, why?

B4505 Direct airflow control from 1.8 to .3 - is that to stop it from going too far before you begin correcting?

B4309 Throttle cracker - very different from the 2000 table - what was the reasoning behind this approach and what results has it had on low speed roll, and other driving characteristics?

B4311 Throttle Cracker activate - is the higher speeed to keep it out of the light throttle slow spped roll area?

B4305 Throttle follower - reduced airflow but increased RPM multiplier - what were your thoughts behind that approach?

B5917 Base spark enable - whay change from 69kmh to 410?

B5920 Spark smoothing - what does it do?

I haven't had the courage to try the full tune yet but if and when I do I assume I plug in my VE (mostly), my timing "strategy" (I'm lower in the open throttle areas due to the 11 to 1 compression and 8.8 DCR), And my MAF calibrations?

A lot of this is explained in the idle tutorial (http://forum.efilive.com/showthread.php?t=4661).

Usually, cam'd applications will have problems bucking on decel....except for when they're in DFCO. So, by keeping DFCO on longer or enabling it at lower RPMs, you limit the bucking (and save a little gas).

I changed the idle controls from TP=0% and MPH=0 to TP=1.19% and MPH=2 because it better lines up with the other settings I like (i.e. when throttle cracker shuts off). Leaving a gap between the cracker disable and idle controls enable can leave a 'black hole' of sorts where timing and the IAC is static - there's no active control to be had other than what's in the base timing table.

The factory B4503 setting is 1.3 seconds on the '01-'02.

B4505 is how long the car waits to try and correct idle (when below the 1.19%/2mph thresholds) for being high/low. I use it as a low correction only by zeroing out the high values in B4515. The way I figure, you do the RAFIG process to get idle airflow close. The PCM will add/subtract any day-to-day variation in required idle airflow. If the idle is too high, short term it'll pull timing and shortly there after it will learn itself down. When I rev the engine at idle, there's no reason it should pull desired idle airflow after 1.3 seconds to help get the engine back down to the desired idle speed. It'll come down on it's own.

The new throttle cracker map is what I arrived at to help avoid bucking in cam applications AND to help with rolling idle. By setting the 400rpm row to something like 4.0grams/sec, you're essentially telling the PCM to open the IAC if idle drops that low when the throttle cracker is active. Remember, in this tune if the car is moving 3mph or faster, the throttle cracker controls IAC. If the car is moving 2mph or slower, the idle controls figure it out for themselves. Keep in mind also, the table is interpolated. It doesn't add 4.0grams/second as soon as you drop below 1000rpm. It's added progressively. If 1000rpm is set to 0 and 400rpm is set to 4, it'll add 1gram/sec of IAC every 150rpm it goes below 1000rpm. Works as a great rolling stall saver.

Throttle follower was set that way again based on the characteristics I noticed with my cam'd application starting from an '01 file. The reason I used a lower airflow number and higher multiplier is because the multiplier is RPM based whereas the airflow number is TP% based. I care more about how much follower is applied based on RPM than I do TP% so I can achieve smoother low-end throttle transitions. Check that idle tutorial. :)

Base spark enable - why should the car use the high octane spark for off-throttle timing above 43mph? What's so different above 43mph that the 'engineers' at GM said, "Oh...we're going 43mph. We need to use the other timing table." ;) I changed it to keep this consistent. On-throttle=high octane timing map. Off-throttle=base timing tables.

For the most part, the changes I made should be perfectly safe (except for the timing - run what you feel comfortable with). I don't think I touched your fueling settings. So, yes, run my tune with your timing and fueling. But, take note of the lower RPM timing concepts that I have. Typically, cam'd cars don't need nearly as much timing down low. They aren't as efficient and don't use as much fuel, so why would they need the same or more timing than stock?

:D

[lastcall190]

Wow, it was off by that much? Do u have the log? Is it idling any better?

Haven't fired it up since changing the desired airflow, I will do that after work today. Do you have an email address? I have the log saved in my gmail account but don't really feel like downloading it to my work computer :bash: Thanks.

And yes, even with my old tune it was off by that much. Think that there are heavier problems elsewhere?

-J

[SSpdDmon]

Haven't fired it up since changing the desired airflow, I will do that after work today. Do you have an email address? I have the log saved in my gmail account but don't really feel like downloading it to my work computer :bash: Thanks.

And yes, even with my old tune it was off by that much. Think that there are heavier problems elsewhere?

-J
Looking at the log, the idle looked pretty clean. I replied with an "RAFIG-ified" file myself. http://www.motownmuscle.com/forums/images/smilies/lol.gif

:D

[DaddySS]

A lot of this is explained in the idle tutorial (http://forum.efilive.com/showthread.php?t=4661).


:D

I've read the tutorial about 20 times but I suspect it's one of those things you need to read, do, read, do, repeat...:D

I really appreciate the responses and will go through my tune now to compare.

[DaddySS]

Another problem I see is that the throttle cracker is disabled when the clutch is depressed which as you were mentioning above leaves the idle in no mans land - does yours do that?

[SSpdDmon]

Another problem I see is that the throttle cracker is disabled when the clutch is depressed which as you were mentioning above leaves the idle in no mans land - does yours do that?
I don't think so...then again, I can start my car without having to push the clutch in. :D

[DaddySS]

So question: Once you're out of "idle" paramaters ( greater than than the maximum speed for idle) where does the reference for 0% throttle rpm come from - does it remember iac steps for idle or something similar?

[DaddySS]

Anyone?

[SSpdDmon]

So question: Once you're out of "idle" paramaters ( greater than than the maximum speed for idle) where does the reference for 0% throttle rpm come from - does it remember iac steps for idle or something similar?
You're either in idle mode (where adaptive controls are active) or you're not. If you're asking what the PCM refers to in it's attempt to maintain idle while the car is moving....the answer is pretty much Desired Airflow, Base Spark, and Throttle Cracker (Throttle Follower is based on TPS% so technically it's not for idle, but may be decaying out briefly during idle). Those tables determine where the IAC sits, what it does, and what timing is to be commanded. That's why it's important for the Desired Airflow table to be right. If you don't have an accurate foundation to start from, you're just piling on the band-aids.

[DaddySS]

OK, thanks! That's just what I was asking. So since the throttle cracker is disabled when the clutch is depressed, it is desired airflow and base spark.

Much appreciated!