Floating RPM when AC on

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kapilamuni
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Floating RPM when AC on

Post by kapilamuni »

Hi,
My car is a BMW 525TDS diesel . The AC functions normal with very cold air. Since recently when AC on the engine RPM fluctuates up & down. This has no effect on the cooling efficiency but very annoying. I got the idle RPM increased from standard 750 to 800 , but the problem remains.
The compressor is DENSO 10PA17.

Your advise appreciated.
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kapilamuni
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Re: Floating RPM when AC on

Post by kapilamuni »

It seems no one experienced this type of behaviour before. :(
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bohica2xo
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Re: Floating RPM when AC on

Post by bohica2xo »

Not an A/C problem.

Engine idle speed is controlled by the ECM. Take it to BMW & have them read the codes, something is not functioning properly in the engine controls.

Is this car located in the USA?
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kapilamuni
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Re: Floating RPM when AC on

Post by kapilamuni »

No the car is not in USA.
I have the software and through that only increased the idle RPM. No point in going to the dealer, they don't care about older vehicles. :evil:
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