RE: K-Jectronic adjustment

["Bob Rossato" <bob.rossato@att.net>]

> > When I tried to adjust the mixture however, it got a little weird.
> > Clockwise rotation of the adjustment screw is supposed to enrich the
> > mixture.  However, when I tried that the duty cycle went further towards
> > lean (rich on my meter).
>
> please use numbers.  I'll ignore your weird meter for now.  When you

Sorry, towards 0%.

> adjust the mixture the car *does not get leaner or richer*, the CIS
> keeps is as close to stoich as it can until it runs out of range.

Well, that was my understanding.  However, as I enrich the mixture the rpm
will rise.  If the CIS truly compensates completely then nothing should
change, other than the duty cycle. Or am all wet here as well.  BTW, when I
adjust the mixture I'm turning it only in 1/8 to 1/4 turns.

>
> Waht you are saying is that as you adjusted it, the duty cycle changed -
> turning the screw CW (more fuel) should result in a lower DC %.  which
> is not the way you need to go.

Yes, that is what happened.

> > in a new O2 sensor but the readings are the same, though it hasn't gone
> > towards full rich yet.
>
> Well, new OXS saves me wondering about that... but please, again, use
> numbers for your measurements - what are you calling "full rich"?

Sorry again, 100%

> I would at least check the ground wire at the intake manifold.  That is
> the ground for the ecu - if it is bad everything else will be a little
> off.  Whoa, it is on Audis anyway!  I imagine the rocco would be
> similar.  Also take a look, at and clean, general tune up items just to
> be on the safe side.  Is your timing set at stock?  Run gas tank low,
> get some good premium, execute "Italian tune up" (drive around block, or
> whatever, at high rpms...!), this is just general de-cobwebbing.

I had checked the timing and it was spot on.  I will check the ground wire.
>From a discussion with Orin offline earlier he suggested that the high NOX
may just be from a bad cat and not from running lean.  I checked the plugs
this afternoon and discovered that they are covered in black soot suggesting
that the car is actually running overly rich.  Orin may be right.  Plus
they're the dreaded Bosch platinums. I know, I know. Wrong plugs.  Can't
recall why I used them as I don't like them.  I guess I just had them lying
around and that was convenient at the time.


> Also - when were you injector seals last replaced?  New they are nice
> soft rubber, old they are hard nasty little donuts.

I'll spray some starting fluid around the injectors and see if there are any
air leaks.

Thanks
Bob