OK, I am lost. Can't get truck to idle!!!!! Pulling my hair out.

[willn]

I have put the initial tune on the truck and have played with ALL idle settings. I cannot get the truck to idle. It seems to idle without dying if I let it sit for a hour or more, but if I try it multiple times, it will fire and then just die. ANY help would be awesome as I am out of ideas......


I have a log attached. Don't know if it will help. The only way I could keep it running was to hold the throttle. If I let off, it will die.


Mods:

2001 LQ4 bored and stroked to 408.
317 Stock Heads with Comp Lifters and Comp Springs
Wiseco dished 4.030" 9.5:1 CR pistons
Comp 230/238 .600 .603 @ 114 (Spec'd by Comp to maintain towing ability)
Melling High Volume, High Flow Pump
Cloyes single timing set
All new sensors in the block.
Whipple 2300AX (want to get to about 10-15psi)
Fully built 4L80E
Circle D 278mm 4L80E Torque Converter 2800 stall
Tru-Cool 40K Transmission cooler
1000cc at 43psi FIC Injectors, so with manifold referenced they are about 114lb/hr @ 58psi
Pacesetter 1-7/8" LTs Tri-Armor with true dual 3" custom system
Volant CAI with Scoop
Intercooler Kit - CX Racing 31x12x4
EFI Live V1 going to COS3 and SD tune.
34" Radiator w/ '05 Efans



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[joecar]

Have a read of the first two links:



Idle Tuning
showthread.php?4661-Idle-Tuning-Helpful-Info-Inside (http://forum.efilive.com/showthread.php?4661-Idle-Tuning-Helpful-Info-Inside)
showthread.php?14439-Idle-Tips-amp-Tricks (http://forum.efilive.com/showthread.php?14439-Idle-Tips-amp-Tricks)
showthread.php?5866-Auto-VE-questions (http://forum.efilive.com/showthread.php?5866-Auto-VE-questions)
showthread.php?14153-scan-tool-wont-log-rafig-or-rafpn (http://forum.efilive.com/showthread.php?14153-scan-tool-wont-log-rafig-or-rafpn)
showthread.php?14435-Need-help-Can-Start-Car-but-dies-when-I-give-it-any-throttle-before-going-to-CL (http://forum.efilive.com/showthread.php?14435-Need-help-Can-Start-Car-but-dies-when-I-give-it-any-throttle-before-going-to-CL&p=129519&viewfull=1#post129519)
showthread.php?7011-ETC-cars-and-IAC-parameters (http://forum.efilive.com/showthread.php?7011-ETC-cars-and-IAC-parameters&p=61455&viewfull=1#post61455)
showthread.php?14544-Working-on-my-idle-tune (http://forum.efilive.com/showthread.php?14544-Working-on-my-idle-tune)
showthread.php?14794-Help-with-open-loop-%28cold-start%29-tuning (http://forum.efilive.com/showthread.php?14794-Help-with-open-loop-%28cold-start%29-tuning&p=133446#post133446)
showthread.php?149-Idle-%28Transition%29-Tuning (http://forum.efilive.com/showthread.php?149-Idle-%28Transition%29-Tuning)
Stumble-3-seconds-after-cold-start&p=178921#post178921 (http://forum.efilive.com/showthread.php?14144-Stumble-3-seconds-after-cold-start&p=178921#post178921)
Idle-Tips-amp-Tricks:post#46 (http://forum.efilive.com/showthread.php?14439-Idle-Tips-amp-Tricks&p=193144&viewfull=1#post193144)

More Idle Tuning
showthread.php?t=149 (http://forum.efilive.com/showthread.php?t=149)
showthread.php?t=5866 (http://forum.efilive.com/showthread.php?t=5866&highlight=RAFIG)
showthread.php?p=86553 (http://forum.efilive.com/showthread.php?p=86553) post #17
showthread.php?t=2630 (http://forum.efilive.com/showthread.php?t=2630)
showthread.php?t=473 (http://forum.efilive.com/showthread.php?t=473)

Throttle Cracker/Follower
showthread.php?t=3568 (http://forum.efilive.com/showthread.php?t=3568)
showthread.php?t=4081 (http://forum.efilive.com/showthread.php?t=4081)
showthread.php?t=5406 (http://forum.efilive.com/showthread.php?t=5406)
showthread.php?t=5940 (http://forum.efilive.com/showthread.php?t=5940)

[willn]

Joe, I have been over and over those links. I have searched and searched the forums. Everything I change makes no difference.

I guess I am trying to determine if I have a mechanical issue or a tuning issue. The only thing that makes me think it is tuning is that if I let it sit for a hour or more, it will start and idle fine....

[willn]

Alright, I messed with the tune a little more and now it is idling. I am not sure what I changed that made it work, but it is. The next issue is that when I shift into gear, it dies.

Any ideas? Here is the newest tune with log.

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[statesman]

Have you done a C.A.S.E. learn?

[willn]

I have not because I couldn't get it to idle long enough...

Also, I thought that CASE was only if I was seeing misfires? :confused:

[statesman]

You said in your first post that you put in all new sensors... so I'm guessing you have a new crank angle sensor. I'm also guessing that you might have a new crank angle sensor error, which will need to be learned. Your first priority would be getting it to idle... does the exhaust smell fuelly when it is running?

[willn]

Yes, it does. According to the wideband I am getting pretty rich too. Like 10.5:1 to 11.5:1.

Yes, I did put all new sensors in. Would I be throwing any codes if it needed to be relearned?

[willn]

Ok, I am making a little progress. I am able to idle now, but I think I am getting too much fuel at some point. It will go into gear now, but when I give it gas and it comes back down to idle, it dies. Could this be throttle cracker?


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[willn]

Well, I guess I need to make smaller changes or something. It is now inconsistent on whether it will want to idle or not. The one thing I have noticed is that the commanded and actual AFR is off by a factor of around 2:1. What should I look for in the tune for this?

I am running OLSD.

[joecar]

( to see what you changed, use the compare feature of the tunetool )

[willn]

Joe, thanks, I actually meant that I had changed so many things in the tune at one time, I am not sure what worked and what didn't.

Since that post, I actually was able to take another tune and got the truck running a lot better on idle, but I think it is going too lean now.

Would you mind helping me out?

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[5.7ute]

AFR at idle from a wideband doesn't mean much. Use the bidi controls to find out what AFR & timing it likes & work from there. Best manifold vacuum can be used as a guide.
Also the info from FIC for those injectors is dubious at best. At idle is where these errors have the most effect & can have you chasing your tail.
FWIW my cam idles with a wideband AFR of 16.2 : 1.

[willn]

Thanks for the response. Since my last post I got my WB working and have almost perfect AFR as I have made more adjustments to fueling and spark.

Truck is now idling well and will go into gear without dying. The problem I am having now is that whenever I give it throttle, it stalls. From what I can tell in the log, it looks to be related to spark as the commanded and WB AFR are very, very close.

What makes me think spark is that as the throttle increases the spark just completely drops. Totally inverse on the map.


Do you have any suggestions on where I should look for this problem?
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[willn]

Noone have any ideas on this newest tune? I feel like I am very close!!!

[willn]

Joecar?

[joecar]

I'm looking thru your latest file (I am still an idle student).

[statesman]

The problem I am having now is that whenever I give it throttle, it stalls. From what I can tell in the log, it looks to be related to spark as the commanded and WB AFR are very, very close.

What makes me think spark is that as the throttle increases the spark just completely drops.

Yes, you're right... your spark is retarding.


Totally inverse on the map.

No, it's exactly as it is on the map.

Spark 'advance' is just that... it's degrees of ADVANCE!

Positive numbers advance the spark... degrees before top dead centre.

Negative numbers retard the spark... degrees after top dead centre.

When you command -14 spark... you're going to get spark 14 degrees AFTER top dead centre.

Try putting sane values in your spark table... start off with about 4 degrees advance for the low RPM, high grams/cylinder area... and then tune your spark from there.

Also, when you fail the MAF the PCM ignores the high octane table and uses the low octane table exclusively so copy your high octane table over to your low octane table when tuning in speed density.

[willn]

Statesman, thank you very much! I didn't know in SD that the low-octane table was being used. Good information.

I am trying to understand this a little more because I am looking at frame 290 in that last log and it is commanding 11.8 degrees and shows only -1. Where is the other 12.8 degrees?


Also, would you recommend taking all the modifiers out such as IAT spark and ECT spark modifiers so that it uses the low-octane table exclusively?

[willn]

Statesman? Joecar?

[joecar]

Too see where the other 12.8 degrees are going, log the EST pids.

Frame 290: something weird is happening here in response to throttle blip.

[statesman]

Also, would you recommend taking all the modifiers out such as IAT spark and ECT spark modifiers so that it uses the low-octane table exclusively?

When you fail the MAF it will ignore the high octane table... It will then only use the low octane table and the modifiers. Taking out the modifiers won't force it to use the low octane table... failing the MAF is what forces it to use the low octane table.

[willn]

Well, what I meant by using the low-octane table exclusively is that there would be no modifiers at all and what you see is what you get kind of thing from timing. In other words, what I would command on the low-octane table would be exactly what I would see commanded without modifiers. Is that recommended?

[willn]

OK, made a couple of movements today. The truck is still stalling, but it seems to be when I am turning the wheel, almost like the load of the power steering kills it??

I did see that in a couple of places that I was getting some burst knock. What is the recommendation on this?

I was also getting some regular knock, but I am not sure if it is true knock or not. My exhaust is too loud for me to actually hear pinging in the engine also.

Any ideas from here?

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[willn]

Another log after determining that the sensitivity was not configured on my knock sensors. That seems to have helped some, but I am still getting knock and not sure why. The timing does seem to be better. I also zero'd burst knock table out and that seems to have helped with the power loss.

The latest log shows no retard based on any modifiers. I would still love to figure out why the truck stalls though. It mainly does it when I am dropping back down from higher RPMs.

Thinking maybe it is related to throttle cracker?

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