Rpm Surging

[Wheelspk]

Hello everyone!

My RPMs keep Fluctuating/ Surging what could be causing this ?
When in park the rpm goes up and down and i can hear the cars sound changing as the rpms move up and down.

Video:

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Also there is a annoying whining sound when i cold start the car which tones down when the car is warmer but is still there, me thinking its bad PS oil i changed it to new oil , bleed the system but the whinning sound is still there.

Video:

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[ray_hennig]

My RPMs keep Fluctuating/ Surging what could be causing this ?

What sort of car?

And the videos are unavailable. At least, for me.

R

 

[MeQ]

For the idle, spark plugs (check correct gaps or replace and check) and coil packs.

I would start with the plugs and go from there.

 

[Wheelspk]

What sort of car?

And the videos are unavailable. At least, for me.

R

Sorry forgot to mention my car model my bad.

Its a 2012 c63 amg w204

 

[Wheelspk]

For the idle, spark plugs (check correct gaps or replace and check) and coil packs.

I would start with the plugs and go from there.

Have changed the plugs , coils and gaped to .040
The idle surge remains.

 

[noogieman]

Could you have a vacuum leak from intake hoses?

 

[AMGeed]

Could you have a vacuum leak from intake hoses?

+1. That was the first thing I thought of when the OP mentioned surging RPM.

 

[RichardF]

I had similar, traced it to the MOT evap valve jamming open.

 

[noogieman]

+1. That was the first thing I thought of when the OP mentioned surging RPM.

Intake hoses gets hard and brittle with years, they won't hold tight, could result in surging RPM

 

[Wheelspk]

Found the issue, it was the throttle body plate, it had a nasty hole in it…had to open the whole intake conform and found it…replaced it a used one and that fix the Rpm surge.

 

[BlackC55]

An air leak is the most common thing.