mr5994

Yeah....from what I've read, it's a little on the low side.......however because fuel pressure doesn't drop while its stalling/stumbling.....it would not appear to be the cause of my issue.

One other thing that I had forgotten to mention......after starting a cold engine....there is no issue at all.....foot on brake, in drive idle is around 700 rpm and no hint of stalling/stumbling. Drive around a few minutes and stalling issue is back. Maybe open loop idle is set a little higher in the ecm than closed loop?

Will do, thanks for the suggestions.

I have an 03 Suburban 5.3 that stalls only when I have my foot on the brake while in gear.....no issues at all idling in park or driving down the road. Prior to stalling, RPM will drop below 400 and volt gauge will drop below 12. ECM is not throwing any codes. What I've done to date: Replaced battery Replaced alternator Cleaned MAF Replaced MAF with known good unit Checked fuel pressure: 45 psi in park at idle, 55 psi in park at idle vac line off reg, 45 psi idle in drive, foot on brake while nearly stalling at 400 rpm. What should I try next? I see that a failing crank sensor will often exhibit the same symptoms....anything else? I do have a blue tooth OBD2 scanner.....so if there are any parameters I can monitor to help diagnose the issue....I'm all ears. Thanks in advance.