Hard to start when hot

[W_D_R]

When I start the truck at operating temp it will idle at very low rpm and die. If I aplly slight throttle it will start and run fine. What should I adjust to cure this problem?

Truck is a 97 yukon 383 with marine intake and 0411.

Wes

[Ls1_Rulz]

Table B4307

[WeathermanShawn]

Table B4307 Desired Airflow is a good place to start (as previously mentioned). Usually that means adding air. You can look at some of the Idle Tutorials on how to do that.

Another Table that can really help is Table B4343 Startup Friction Airflow Correction (depending on your OS). You can easily add 1-2 g/s to the specific ECT you are having trouble with. That extra air decays rapidly..so you just get the additional airflow at startup.

Hope that helps.

[W_D_R]

I tried adjusting both of those tables with no success. Here is my tune.

[WeathermanShawn]

Well if you legitimately adding Airflow and that does not work..I would start thinking Base Spark in Gear. Perhaps it is too low?

Quite frankly, Idle Tuning problems are tough to diagnose. I actually had a lot of success following the Idle Tuning Tutorial..http://forum.efilive.com/showthread.php?t=4661. (http://forum.efilive.com/showthread.php?t=4661)

I literally went through line by line, especially on modifying the Idle Learning Parameters. I spent about 2-3 days with my car until I got it down.

Have you modified your B3605 Table? Is it really 14.68 AFR all the way across (stock). If it is a hot start and too lean, you can stall. I am just throwing a few things out there. Adding Airflow usually works..:).

Good luck..

[W_D_R]

Thanks weatherman! I went through that tutorial and changed a few items. It did not work at first but after a few days the truck starts without hesitation.
Wes

[WeathermanShawn]

Good Job!

Let us know how it goes. Then the next hot start-up problem someone has..you can give them some help..:cheers: