E38 5.3L w/CAM starts and dies cold/warm starts up great at normal temp

[Maglin]

My issue is the truck will start up cold for about 1-2 seconds and then just die as if almost the fuel was shut off when cold. When around 160*F it will start up to set idle for 1-2 sec's then drop down to about 300-400 rpm and struggle for maybe 20 seconds and either come up to it's idle speed and behave normally or die. The next attempt to start it will usually idle fine. I had a log of it but didn't save it and updated my VCM suite and lost the data. Rookie mistake but the TPS% never moves when it dies. It stays pretty solid at 18-19%.

So I've finally got this 224R cam to idle fairly decent. Ie it idles at 675 and doesn't dip or die coming to a stop and zero surging. It used to start up cold no problem and then not want to start when hot and would barely idle. It's now the opposite and I've tried doing some drastic changes all around and I just can't seem to get it figured out. I'm wanting to do this while staying away from the idle tables that are now fairly dialed in for a good running idle. I have it on the VVE table and MAF above 3000 rpm and have been working on the cruise section of the VVE table. Give me some idea's. I was thinking that the ECT multi airflow table would maybe help me but it didn't.

I plan to get a log of the start up tomorrow but was hoping I might get a direction I can try to go for this. Thank you.

[SultanHassanMasTuning]

check your commanded fueling when cold

[Maglin]

Turned out I had to add more %Max to allow the throttle to open more on cold, warm starts. Doing that revealed I indeed had to much min idle air. Once I got those close all is with in reason now. I'm kind of glad I figured it out on my own. I noticed it was adding plenty of fuel. But the relative throttle was very near 3%. Just wanted to put an update on this.

[SSstoked]

I was going to recommend checking your percent max-brake value under IDLE AIRFLOW tab.. I had the same issue

[mowton]

The E38 Idle setup/tune is a bit different than the GEN III. As there are no Idle Desired or LT/STIT PID's to monitor, the top level procedure is to set the Maximum opening (Percent Max and Percent Max - Brake espectively) of the blade for both rolling and stationary (see above), the minimum (See Final Airflow Min in the Editor) and then the Idle Proportional and Integral corrections manage the "in-between". The timing (as modified by the Over/Underspeed Adaptive spark) and the TPS% are great indicator as to how good/bad you have your airflow set.

Ed M

[BigMike42]

I can't view the tune at work, but it does sound like the cam needs more air than being allowed due to the max idle area restriction.