Missing the Buz -or- My Fuel Distributor is too quiteandmy car runs like

David Head v8q at bellsouth.net
Wed Aug 14 14:34:20 EDT 2002

I had an 87 with a worn out aux contact - it would drop power to it, the wastegate
freq valve etc...

Ameer Antar wrote:

> you're right, I forgot that open-loop is still sends a signal to the freq.
> valve. But if it's not making noise, something is keeping it from getting
> the signal, or it is getting signal and it's not responding. I think a look
> at the wiring diagram for the car might help if any connections are loose.
> -ameer
> At 12:39 PM 8/14/2002, you wrote:
> >Not true - the frequency valve (duty cycle) will go to preset settings in
> >the open
> >loop mode (low temp, O2 sensor open/shorted, WOT switch actuated)  - but it is
> >operated from the ECU/fuel pump relay and is always on when the car is
> >running.
> >
> >Ameer Antar wrote:
> >
> > > Turbo motors use a frequency valve which buzzes along to regulate the
> > > mixture. It sits sorta near the fuel filter. If the system is in open-loop
> > > mode, it shouldn't buzz. Maybe the system can't get into closed-loop mode.
> > > A bad o2 sensor, or any other sensor might cause this. I'd test the
> > > resistance of the valve itself to make sure there's no short or break in
> > > the windings too. Is the duty cycle showing up on the freq. valve's signal
> > > wires? If the signal is there, the valve might not be responding any more.
> > > Of course, you should check for vac leaks and clean or replace any aging
> > > parts for the entire system. Good luck.
> > >

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