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View Full Version : What causes surgin/cruise control?


pkincy
January 29th, 2006, 12:04 PM
Tell me if my simplistic thoughts are right.

Surging is too little air

Cruise control is too much air.

Perry
TAQuickness
January 29th, 2006, 12:38 PM
In very basic general terms:

surging is spark

cruise control, too much air

stalling, not enough air, rich condition.
pkincy
January 29th, 2006, 12:46 PM
Yet, most tuning manuals/stickies/recommendations control surging through the throttle followers or running airflow rather than the timing table.

Why is that?

Perry
TAQuickness
January 29th, 2006, 01:57 PM
The stock idle spark tables do a good job for the most part. When you combine the effects of the follower/cracker and DAF with the spark tables, the PCM starts over/under correcting before fully returning to the idle state.