88 5kq - Intermittant Hard Starting

[Huw Powell]

>>Symptoms:
>>88 5kq - no turbo - NF engine

> The solution seems to adjust the idle mixture (3 mm Allen) in order to get
> the O2 sensor working at idle.

> I was thinking of adjusting the idle mixture by watching the DVM. When the
> O2 sensor starts working (swinging), the mixture is on the low (lean) side
> of the DPR's control range. Maybe adjusting another 1/4 turn or so to richen
> the mixture will get the mixture centered in the DPR's control range.

To make this adjustment without a CO meter, you hook up a milliammeter 
in series with the DPR and adjust the static fuel mixture at idle until 
the DPR current swings back and forth (with OXS voltage) around 0 mA. 
(it will go back and forth a few mA - you need a fine scale on your 
meter).  It helps to make a harness from male to female for the DPR 
plug, but you can get by without.

And as you say, it might need to be richer to enable the ECU to get it 
to swing at all.

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/