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6.0vortecchevy
February 24th, 2011, 03:04 AM
I have a gmpp hot cam in my truck that just doesnt seem to want to start right. I got the cold start up, but worm is a little troubling. My window computer just craped out so right now im on my mac so i cant do any tuning just yet but i would like to get some opinion on what changes i should make. thanks.

http://s261.photobucket.com/albums/ii41/vortecchevy/?action=view&current=DSCN0699.mp4

joecar
February 24th, 2011, 05:24 AM
You have a MacBook...?

If you install Boot Camp it will allow you to partition the hard disk and install WinXP so you can then run the EFILive software.

joecar
February 24th, 2011, 05:26 AM
More info on idle tuning:




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?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)

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)

6.0vortecchevy
February 24th, 2011, 05:57 AM
Yea ino i need to install windows on this computer but ive never gotten around to it. Im going to check out those threads but my idle is fine its just warm starts.

6.0vortecchevy
February 24th, 2011, 06:00 AM
ok thank you i can see how those are going to help me.

LSRacing
March 5th, 2011, 03:47 AM
Assuming this is a LS1 Gen 3 controller, 4.8, 5.3 or 6.0, Add more start up fuel to the ECT table for start-up. Increase Table B3604 from 80 degrees up all 24x cycles. Make it the same as the 70 degree C Row. Then play with B3632 to tweak it a bit. This should help your hot start problem. Post your tune when you get a chance and a start-up log and we can take a look.

6.0vortecchevy
March 5th, 2011, 05:12 AM
Ok thanks lot I should have my windows in about 3 days so illl shoot you guys a log and see what i can do. And also if i stab the gas real fast it will die when coming back down to idle.

6.0vortecchevy
March 7th, 2011, 08:32 AM
Ok what exactly do you want to look at for the log? What pid's?

WeathermanShawn
March 7th, 2011, 08:52 AM
Vortec:

Though this Tutorial is primarily written for LS1's, it is a good 'Template' to follow:http://forum.efilive.com/showthread.php?14439-Idle-Tips-amp-Tricks

Also check out Joecar's links in Post 3:http://forum.efilive.com/showthread.php?15789-Cant-get-start-up-right&p=139129&viewfull=1#post139129

That should be a good start for you..

6.0vortecchevy
March 10th, 2011, 12:23 PM
OK so i got the start up really nice, but why is it every time i reflash its starts PERFECT. Starts perfect a few more times, but then ill let my truck sit for a little and the starts up begin to get worse and worse. So ill reflash it again, presto perfect starts. Whats the deal?

WeathermanShawn
March 10th, 2011, 01:17 PM
Vortec, we would need some more information about your Tune & Log.

Are you Closed-Loop or Open. Are you MAF or SD. How are you controlling your fueling..I.E. Trims, Idle Air..are you monitoring with a wideband..

From my experience..without a log (and Tune) we will just be guessing. The trick with Idle is to always know which Table is in play..hence the log..:).

swingtan
March 10th, 2011, 01:37 PM
I'll guess it's "idle learning".

I've seen this happen a bit before. You flash a new tune in and clear the learnt data, the car idles fine. Then over time the PCM learns incorrect idle data and messes up the idle calibrations. To test this, let the idle go "bad" then just perform a PCM reset to clear the data. Restart the car and see how it goes. If it idles fine, you know it's most likely the learnt data.

There are times when the engine wants slightly skewed values to give a desired idle. For example, some cams may want a higher commanded airflow than is "technically" required. They will idle smoother if they are pulling a little bit of air out, possibly due to the speed that the PCM and cracker react. Once you get it right, the PCM starts to learn that it needs to pull air, so it sets this up in "long term" idle adjustments or "learned" corrections. If you reduce the learning cels a lot, it may help to keep the idle stable over a longer period.

Maybe try zeroing out the bottm few cells in B4512 and B4514. It may help... it may not....


Simon

6.0vortecchevy
March 10th, 2011, 01:57 PM
thats exactly what its doing, every time i reflash its perfect. And im going to post my tune up in a second just got to get on my windows. And ill get a log tomorrow. But im not to clear on which PID's you guys want to look at.

6.0vortecchevy
March 10th, 2011, 02:11 PM
10105

6.0vortecchevy
March 10th, 2011, 02:14 PM
Vortec, we would need some more information about your Tune & Log.

Are you Closed-Loop or Open. Are you MAF or SD. How are you controlling your fueling..I.E. Trims, Idle Air..are you monitoring with a wideband..

From my experience..without a log (and Tune) we will just be guessing. The trick with Idle is to always know which Table is in play..hence the log..:).

its usally when the truck is warm and in closed loop. Im MAf and i had a wide band but the harness burned up. So i have nothing to go off from that point.

WeathermanShawn
March 10th, 2011, 02:23 PM
Perhaps Simon has a list of Idle Pids he recommends. If not I can probably work something up in the next day or two. I usually log all the regular pids..I.E. MAP, RPM, ECT, IAT..etc..both HO2 Pids, and a few Idle Air Pids..Keep it at 24 channels or less.

Are you talking a hot re-start?

Like Simon said a lot of it revolves around the Idle Learning cells. I use SSpdDmon's Link for those cells..http://forum.efilive.com/showthread.php?4661-Idle-Tuning-Helpful-Info-Inside

Your Tune looks MAF, Closed-loop. Are you NB's in good shape?

Thats all I can think of for now.

6.0vortecchevy
March 10th, 2011, 02:30 PM
Yes hot restarts and yes there perfect.

WeathermanShawn
March 10th, 2011, 02:51 PM
Yes hot restarts and yes there perfect.

Usually a very easy and simple fix is to add +2-4 g/s in Table B4343 from 60C-140C.

6.0vortecchevy
March 11th, 2011, 09:12 AM
Thanks guys with your tips the start up are perfect now. Im going to get a log anyway tonight. Since i have a few more things I want to address, po300 since i put a higher stall in. Not sure what table controls the misfires, and every time i stab the gas hard it will stall. But like i said ill get a log for you guys tonight to see.

6.0vortecchevy
March 11th, 2011, 12:34 PM
10111

OK heres a quick log i just took. And does anybody see anything thing in my tune that would make my tran skip second and go right to third on light throttle. It rarley does it but its anoying when it does. And in this log i made the truck stall.

WeathermanShawn
March 11th, 2011, 01:39 PM
Vortec:

Here are the Pids you should be logging (depending on OS). This will show your O2's, Trims, Fueling, Spark, and Idle Air. I prefer to keep them all in Metric where possible.

Is your Tune 100% stock? Also, I did not see any changes to your posted Tune from the Idle Tutorial(s). Have you tried any other changes to your Tune.

Other than cam, anything else not stock?

6.0vortecchevy
March 11th, 2011, 01:49 PM
Ok im going to get a log right now, thanks. No its not stock, and i added +4 to table b4343 And zeroed out much of my learning. Its has a cam Lt's and thats it.

6.0vortecchevy
March 11th, 2011, 02:27 PM
10113

OK heres the pids you selected, and once again I made the truck stall.

WeathermanShawn
March 11th, 2011, 03:05 PM
The first thing that is pretty obvious is that you are extremely lean. Your overall LTFT's are over 17%, and occasionally max out at +25%. You can't hold Idle being that lean.

Also, there is a wide range from your High-Octane Spark Values and Base Spark. So when you flick the throttle you are going to High Octane, then the spark drops dramatically as your go below 1.19% TPS (Base Spark). That will also cause a vehicle to stall.

I don't know why you are so lean. Your NB's look fine at cruise, but very slow at Idle. Perhaps they are struggling with adding fuel..

To get your fueling back to normal would take an extremely large adjustment to your MAF Table B5001. At this point I might suspect an exhaust leak, improper NB wiring, or some other issue.

Perhaps another Tuner can look over your Tune & Log and make a suggestion. Your just way too lean..

6.0vortecchevy
March 11th, 2011, 04:02 PM
Your right i remember when i had my WB on it said 17.1 before it burned up. Well I do have two point in my exhaust that leak. Im going to play around tomorrow and see what i can do.

6.0vortecchevy
March 12th, 2011, 04:51 AM
B5001 say not to make changes to that table unless MAF has been altered. Could i just fatten her up at low rpm's. Doing it blind without a wbo2.

6.0vortecchevy
March 12th, 2011, 12:14 PM
OK i got it to not stall when i brake stall her up, its Allot better but not perfect. I add some to the main VE table. But im still getting a little surge after i brake stall it. So Im going to mess with it more tomorrow and read that tutorial.

WeathermanShawn
March 12th, 2011, 01:20 PM
With a cam you can add some to Table B5001. Try +10% everywhere. See if your LTFT's decrease proportionally.

However with your LTFT's running at +25%, it has to be one of the exhaust leaks messing up your Trims. I usually don't mess with the VE until the MAF is good..

6.0vortecchevy
March 12th, 2011, 01:25 PM
Ok ill try that tomorrow and take another log.

Edit: well i just tried that and it seems to make the surge worse and stall.

WeathermanShawn
March 12th, 2011, 02:33 PM
If you address the exhaust leak(s)..eliminate your +Trims and follow the Idle Tutorial(s) I'll be glad to assist. Otherwise, I think we are just going in circles...:). You have some serious Fueling, Spark, and Airflow issues with your current Tune. Read through the Idle Tutorials and make those changes.

Good luck..

SSpdDmon
March 13th, 2011, 06:36 PM
10111

OK heres a quick log i just took. And does anybody see anything thing in my tune that would make my tran skip second and go right to third on light throttle. It rarley does it but its anoying when it does. And in this log i made the truck stall.

Once you figure out your air/fuel/spark, tuning an A4 can be easy. Start here - http://forum.efilive.com/showthread.php?5876-Tool-to-help-tune-A4-shift-points...&highlight=shift and load in your current tables. It may reveal any overlap that causes the trans to skip a gear.

6.0vortecchevy
March 14th, 2011, 01:57 AM
Thanks alot guys, next week the trucks going in for a whole new exhaust system. So after that all take another log and see whats going on.