Sticking throttle

[Voodoocars]

The in laws hve a 2002 s class 320d straight 6. The accelerator pedal has been sticking down a couple of times when pulling away after first starting up. Do these cars have fly by wire?
She says she has had to lift the pedal back up with her foot. I havnt had a look yet so any info would be great. Thanks.

 

[Voodoocars]

Just got a look at it. When the pedal is first pressed it feels odd , like it has to overcome the start of the spring but the second press is ok. Strange.

 

[WG M-B]

It's an electronic pedal