Need help with lean "choke" for TBI

[GMC Truck]

Truck lean pops up thru the TBI when its really cold. What would I need to change in TunerPro to richen this up? Could this be the AFR vs Temp? Also what is "idle speed Deadband" used for? 7747 ECM with $42 mask.

 

[GMC Truck]

Looking into it, it might be that I need to change the "Power enrichment AFR vs RPM"? Maybe not since it runs ok when its warm.

 

[dave w]

I think maybe compare these settings with yours. I usually change one or two settings at a time.

dave w

 

[eagle mark]

One thing to remember before making any of these little changes are get your warmed up driving fuel maps dead on first! Because all these other settings are based of those!

 

[GMC Truck]

Yeh it drives perfect when warmed up so i'm afraid to change anything? My problrm is when I start it up and its real cold (15 degrees) and I try to drive it before its "completly" warmed up it will lean pop up through the tbi and buck and jerk. I know it just needs richened up a tad but there are so many things that affect the "cold choke" settings i'm not sure what to change first to try??

 

[dave w]

I think I would change the Open Loop Air Fuel Ratio vs. Coolant Temp first. I would try a 0.5 richer Open Loop Air Fuel Ratio for the Temperatures 7C and 16C.

For example if 7C Open Loop Air Fuel Ratio vs. Coolant Temp was 11.3, then I would richen the setting to 10.8. ( 11.3 - .5 ) = 10.8

For example if 16C Open Loop Air Fuel Ratio vs. Coolant Temp was 11.8, then I would richen the setting to 11.3. ( 11.8 - .5 ) = 11.3

Keep track of all changes.

dave w