Cold start question.

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October 20th, 2011
12sec.5.3

Cold start question.

I'm having an issue when i crank up the truck for the first time of the day or after it sits a while and cools off to ambient temps. It will not idle on it's own, I have to hold it at roughly 2k rpm for 30 sec to a minute before it'll act right. It also goes really rich upon starting, I can actually watch the WB go from 15 down to 11.x. My tune is far from perfect but I'm fine with it, I just enjoy messing with it and exploring. Could someone put me in the right direction. Again, I'm not aiming for perfection, with the combo that I'm running it would really need to be retuned professionally.
October 20th, 2011
12sec.5.3

Nevermind guys, I just figured it out and it took all of 5 minutes. Thanks anyways!
October 20th, 2011
joecar

What was the answer...?
October 24th, 2011
12sec.5.3

Well, I thought I had it but evidently not! I'm so confused lol...
I went back to my previous post from a few months ago and revised some of the tables with some stock tunes that I downloaded. It seemed to be working great until I tryed to crank it up on a cold morning after the front came through. Maybe I can post it up here and you can take a look at it. I know my MAF could be off bc I've been playing with it. It's my stock MAF from my 2000 5.3 set up but behind it is a 90mm TB and l76 intake on a 370. It's not a very common combo so I guess that's why I have so many issues.. It's a real mix-match but runs really strong :hihi:
October 24th, 2011
minytrker

Either your idle airflow or fuel is probably off. Post up the tune and a cold start log.
October 24th, 2011
12sec.5.3

I have a feeling it's a little of both. I'll post it when I get home. If you don't mind, tell me wt tables to look at so I can look into it.
October 24th, 2011
joecar

Did you already read thru these, they have what you're looking for:

Quote:

Idle Tuning
showthread.php?4661-Idle-Tuning-Helpful-Info-Inside
showthread.php?14439-Idle-Tips-amp-Tricks
showthread.php?5866-Auto-VE-questions
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
showthread.php?7011-ETC-cars-and-IAC-parameters
showthread.php?14544-Working-on-my-idle-tune
showthread.php?14794-Help-with-open-loop-(cold-start)-tuning
showthread.php?149-Idle-(Transition)-Tuning

More Idle Tuning
showthread.php?t=149
showthread.php?t=5866
showthread.php?p=86553 post #17
showthread.php?t=2630
showthread.php?t=473

Throttle Cracker/Follower
showthread.php?t=3568
showthread.php?t=4081
showthread.php?t=5406
showthread.php?t=5940
November 1st, 2011
12sec.5.3

2 Attachment(s)

Here's a cold start log. Notice the first cranks are at 0% tps then i had to give it some to get it running. Also threw in my current tune.
November 1st, 2011
minytrker

List all your mods.

Your cranking ve and timing tables dont look right, they need some work.
November 1st, 2011
12sec.5.3

6.0 bored to 370 ci., L92 ported heads , L76 intake, 90mm tb, comp. cam custom grind , 42 lb inj., headers, intake, and wtever else
November 1st, 2011
12sec.5.3

Quote:

Originally Posted by minytrker

Your cranking ve and timing tables dont look right, they need some work.

Cranking VE is from a 2004 stock 6.0 truck.
November 2nd, 2011
minytrker

Quote:

Originally Posted by 12sec.5.3

Cranking VE is from a 2004 stock 6.0 truck.

I just knew it didnt look right for a 5.3, I didnt spend alot of timing looking through your tune but those were the tables that jumped out as not looking right. Have you tried the 5.3 VE? I looked on my base tunes I use to fire up 6.0 swap trucks my cranking VE is alot closer to the 5.3 than the 6.0. I would also load in stock timing tables and see if that helps, you have to much timing down low.
November 2nd, 2011
12sec.5.3

1 Attachment(s)

Attachment 12193I changed my cranking VE to a stock 02 camaro and my base spark tables to some others I had and it still aint right. For some reason i think its fuel AND IAC related. it wont stay running unless i keep tapping the pedal.
November 2nd, 2011
ScarabEpic22

You're going to have to tune the idle and IAC, simply copying and pasting other cranking VE and idle VE tables from other engines might get you close, but it wont be perfect unless you spend the time to tune it. Check out the links joecar posted a few posts up, they're time consuming but with a unique combo like yours you're probably going to need to spend the time and dial it in.
November 2nd, 2011
12sec.5.3

It seems as though something is really off though and I can't put my hand on it. I'm not at the point of fine tuning the idle to perfect, I'm simply trying to get it to crank without me having to sit there and play with the pedal until it warms up some. Sometimes I think it could be a small intake manifold leak because it acts right after it warms up.