911 Mod 83 Taktventil 930 110 095 01 need help

[HKZ Bob]

Dear All,
I am having trouble with the Taktventil. This unit makes a winning noise
without the ignition on.

In english: Frequency Valve

Who knows the function of this part. In the Porsche PET it is No 77.
How can the circuit being tested and why does it makes this terrible noise.






Best regards
Bob

[Flat6pac]

The unit is controlled through the harness connection plug left side on the shock rail and is fed from the rear control panel and under the right seat.
Unit is suposed to squeel in the run position of the key
Bruce

[HKZ Bob]

Thank you Flat6pac,

My unit squeel with no key in the ignition.



It looks like a problem with the wiring of the OXS relay. The alternator was rebuild
and maybe the cable of the OXS relay is wired hot.
I will check this or the relay is bad?

Where is the location of this OXS relay?

BR Bob

[HKZ Bob]

Somehow the OXS relay is involved to shorten the Frequency Valve circuit

[Won]

The OXS relay is under the passenger seat. It's a standard cube relay and the only one there. It could be that the relay is sticking and causing the frequency valve to buzz with ignition off.

The frequency valve controls the fuel mixture by varying the duty cycle which is determined by the lambda brain under the passenger seat.

[HKZ Bob]

Is this the correct one?



BR bob

[Won]

Bob, that's the one.