4K QUATTRO IDLE PROBLEM AFTER INJECTOR OVERHAUL

[Ado Sigal]

Lean is anti and rich is clockwise. Move the adjustment tool by only 
degree or max two at the time slowly until it runs smooth, then adjust 
revs with idling screw, and use it like that for a few days until it 
settles than fine tune it again, or rev it for a minute or two above 
3500 revs, and fine tune it there and then. Make sure also that the 
throttle switch is working correctly, and you follow Co tuning procedure 
for your model, they differ slightly, although basic procedure is same.
As Huw said, don't forget to remove the tool and blip the throttle and 
the rest.
Happy tuning,

Ado


Huw Powell wrote:

> 
> 
>> I recently went to an independent shop in the area that flushed my
>> injectors, replaced two injectors and all injector seat seals. Car
>> runs much better, as one injector was squirting, not spraying.
>> However, now, the car idles low, and when the car is warmed up, when
>> I let off the accelerator (while driving), the idle dips to about
>> 5-600rpm, which causes stumbling to the point of almost stalling.
>> Then it immediately spikes back up again to normal 
> 
> 
> It sounds like your car was "tuned" to run with air leaks around the 
> injectors, and possible inaccurate fuel delivery as well.
> 
> If the baseline fuel mixture (adjusted with that 3mm hex while observing 
>  actuator current or measuring CO) is a bit off, the idle hunting you 
> describe is very common.
> 
> You might be able to adjust it by "ear," if you are lucky.  get a handy 
> 3mm T-handle hex key and find the hole between the air boot and fuel 
> distributor.  Make sure the socket it goes into is clean, some carb 
> cleaner can help here.
> 
> While adjusting, keep track of exactly how far you turn it, and which 
> way, in case you mess it up more than you fix it.
> 
> The odds are, the car was running lean, and so the mixture will have 
> been set richer to offset that.  So while the car is idling warm and 
> exhibiting the idle hunt, you want to carefully turn the screw 
> counterclockwise, about 1/8-1/6 of a turn at a time.  After each small 
> adjustment, remove the tool and blip the throttle to let everything 
> settle down.  You might manage to "tune" the problem out.  Especially if 
> this is all it is.
> 
> You'd still better take a good look for air leaks, loose hoses, etc., as 
> some may have been knocked around while the car was worked on.
>