Tachometer and economy control

[E.serg 535]

Hi guys
When I turn the ignition off and take the key out in first minuet
the tachometer jumps 3000-4000rpm, economy control gauge moves too and I hear all kind of buzzing noses.
I notarized the buzzing nose even after when I start the car and get 2000-3000 rpm the buzz continues for 4-7sek. then it’s gun till next start and it is coming from driver side. (in winter its lauder )
Any ideas? Please help.
Thanks.

[E.serg 535]

my car is 535 manual ,1989

[ukm5]

the early E34s did have an issue with the tachometer jumping after turning off, but not as high as your suggesting, they did do a recall to fit a diode somewhere, buts its not needed mines always done it for 16 years!

however i cant say thats whats wrong with yours as from what you say it jumps too high, buzzing noises are usually the climate control vavles shutting down inside the dash.

where does the buzzing come from on the drivers side?

[632 Regal]

as in the buzzing sound, does it sound like someone is remote controlling mysterious stuff under the dash? If so thats normal.

As to the jumping tach and eco gage its probably used up capacitors and crap in the back of the dash cluster...there is write ups for resoldering in new ones if you search.

[E.serg 535]

the early E34s did have an issue with the tachometer jumping after turning off, but not as high as your suggesting, they did do a recall to fit a diode somewhere, buts its not needed mines always done it for 16 years!

however i cant say thats whats wrong with yours as from what you say it jumps too high, buzzing noises are usually the climate control vavles shutting down inside the dash.

where does the buzzing come from on the drivers side?

Thank you very much at list I don’t have to worry about this one.
The buzzing noise I mostly hear behind the dashboard more likely inside the hood ( closer to the power distribution box)

[E.serg 535]

Thanks , I am going to change the bulbs inside the dashboard and I will chek the capacitors too.

[ukm5]

Thanks , I am going to change the bulbs inside the dashboard and I will chek the capacitors too.

i doubt its the capacitors when it only occurs at switch off

[Interceptor]

i doubt its the capacitors when it only occurs at switch off

Why do you think that? It very well might be the capacitors - they do have the ability to accumulate charge when power is switched off.