1990 200 missing/lean under boost

[David Michael]

53 psi sounds right. Problem I had was that it randomly jumped to 55 psi.

I also replaced my dizzy because a bad Hall sensor was causing a mis-fire.
But again, it was not boost related - it happened all the time.

Have you checked your valve cover gasket and injector o-rings - both common
sources o vacuum leaks (which will cause you to set your base setting
incorrectly)

Not sure what "NB" is but  at WOT, the system is running open loop, and  the
02 duty cycle goes the a fixed number (can't remember what - maybe 68%).

A boost leak will usually result in black exhaust smoke ie - very rich

Dave

On Thu, Jun 9, 2011 at 10:49 AM, David Yentema <yentemad at rider.edu> wrote:

> These were the fuel pressures I got last time I checked:
> cold control pressure 22psi
> warm control pressure 53psi
> system pressure 84psi
>
>
>
> On Thu, Jun 9, 2011 at 10:31 AM, David Michael <adavidmichael at gmail.com>wrote:
>
>> It's a long shot, but have you checked the control pressure? Moreover, if
>> you can safely do so, you may want to figure out a way
>> to monitor conbtrol pressure under boost.
>> The control pressure is supposed to be very steady after the car warms up,
>> but I had a control pressure regulatory go bad on me; it increased the
>> pressure (leaned out the mixture) by a few PSI randomly. The failure was not
>> related to boost, but if the control pressure is wrong, nothing will work
>> properly. Remember, HIGHER pressure means LESS fuel....
>>
>> Dave
>>
>
>
>
>