Re: Idle Control (OOPS!)

[knut.s.grimsrud@xxxx]

It has been pointed out to me that I unfortunately got a little 
sloppy in the way I wrote this posting resulting in an inaccuracy in 
the description of the mixture surging. When the engine is stone 
cold, the lamda ECU runs the car in a fixed mixture mode and does not 
use the input from the lambda sensor to regulate the mixture (via the 
signal to the frequency valve). The period where the car runs in this 
fixed mixture mode is for the first minute or two after which the 
exhaust gasses should have warmed up the lambda sensor. For the 
remaining period of the engine warmup (once the fixed-mixture phase 
is over) the lambda ECU handles the regulation of the mixture and it 
is this phase that the oscillating mixture likely has an impact on 
idle quality.

I apologize for my sloppiness in not clarifying that the mixture 
oscillation I described only applies during engine warmup after the 
very initial stone-cold period (a couple minutes) is over.

Knut