Audi A4 2.0 TDI Rough idle

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Re: Audi A4 2.0 TDI Rough idle

Postby STC » Thu Aug 18, 2016 9:57 pm

you only have control on duty cycle and not frequency right?
Isn't frequency an issue? Just asking...

Yes & No !!

Frequency will not be too much of an issue when you are activating something directly as our IMV, DRV or any electric motor or solenoid as in this case. Just be cautious of going above 90 / 95% duty as the component may or may not like that for any period of time

It could be tricky if there is a PCB and circuitry between the motor & the connector that we can access to control it. I think some fans are like that where the duty from the ECU is in milliamps, is then measured and the electronics in the fan ECU will then do the magic and control the fan. The Circuitry may get fussy about the Frequency.

Can it do any harm to put a faster / slower frequency to it ?? Assuming the Voltage is Correct (ie not push 12v into a 5v circuit) ?? Can anyone here answer that ?

I have not tried it ?

Have a good look on ebay for PWM Motor Controllers, they are available in varying frequencies.

For the £8 it costs this is a well built tool, good quality and has heaps of Diagnostic Value. Don't forget it has no value on its own, you will need some Correct Wattage and Ohm Resistors or a good decade box to keep the ECU happy when you have the components unplugged and this substituted in.

If you get stuck I can post some links.
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