Spark Bouncing Around At Idle

[BowlingSS]

I notice my spark bouncing around at idle (like 10 to 30). What table can I set to correct this if any?

Bill

[turboberserker]

Try setting the base tables and the running tables to the same numbers from 400-1200 and from .40 g/cyl and below. All of my tables are set to 18*, and while I still see some spark bounce from other tables its only 1-3*.

I noticed if your base tables are set to your idle timing and you leave the running tables alone it tries to interpolate between the two under certain circumstances (mine tried to bounce between 10 and 32* :()

[Black02SS]

Look at these tables as well as monitor the IDLE DMA Spark PID

{B5934} Idle Flare Control
{B5935} Idle Overspeed Error
{B5936} Idle Underspeed Error
{B4353} Idle Spark Control Delay

That should tell you exactly where it is coming from.

[dbaxter_ss]

You can also monitor with scan the multiple spark pids that may help narrow what area is pulling or adding timing.

[Delco]

Idle control on a LS1 is controlled predominately by spark , hence you idle spark moving around , the IAC is only used to make large changes and to go to a predicted value.

Any car with a cam is going to have a large idle spark variation as the pcm tries to control the idle rpm withing the boundaries you have set , if you want more of a slow lope then open up the idle values
{B5935} Idle Overspeed Error and
{B5936} Idle Underspeed Error