GEN 5 Camaro goes lean after 5-10 minutes. Immediately fixed after re-flashing ECM.

[LSxpwrdZ]

I disable post o2 on nearly everything I touch since we don't have emissions testing here and everyone is using cat-less mids/xpipe.

[josephz28]

so let it run ten minutes or go wot is the answer. anyone ever figure out what the actual cause is. doing a buddies 2011 v first e67 i have done. real inconsistent fueling. maf only tune also

[SultanHassanMasTuning]

yesterday i was tuning a E38 camaro and the car is setup in open loop and have no O2 sensors and still has this condition. seems worse without the o2 sensors.

i even did a couple of WOT and didnt clear up until exactly around 10-15 minutes.

flahsing and the wideband peggs to 11.5 at idle and stays there.

[dcpatters]

yesterday i was tuning a E38 camaro and the car is setup in open loop and have no O2 sensors and still has this condition. seems worse without the o2 sensors.

i even did a couple of WOT and didnt clear up until exactly around 10-15 minutes.

flahsing and the wideband peggs to 11.5 at idle and stays there.

As a tuning shop and dyno operator, that must be a huge pain in the ass.

[waynehartwig]

I don't do a lot of E38 equipped vehicles, but I've never seen this problem. Curious, when you flash the ECM, do you shut the rig off and remove the key for like 30 seconds then start?

This has always been a habit of mine and I do it on all PCM/ECM's. Doing this, you also don't have to go through the turn the key on for so long then off for so long and repeat to do things like VIN changes and etc.

The way I understand it is the PCM has two places that hold the program. When you write to it, it's a volatile area. Then when you shut it off for ~30 seconds, it moves the information from that area to a non volatile area. Not sure exactly how this works or etc, but once I learned this and started doing it, I quit having programming issues...