Brake pedal normal in D, no resistance in P or N.

[StokerBlake]

Drove home in wife's w203 sportcoupe (2002 CL203). Brakes working normally. Put car in neutral engine still running and brake pedal goes soft and air sound when press pedal. Put back in drive or reverse, pedal travel normal. Back to park or neutral pedal goes nearly to floor again. Revving engine makes no difference. I'm stumped. Is there something MB specific that could cause this? Any ideas greatly appreciated.

 

[markjay]

I cannot explain it either, because the W203 has a traditional braking system, with a master cylinder and a vacuum servo unit, and so obviously it shouldn't be possible for it to behave like there's air in the system on some occasions and then be fine again.

The only thing I can think of is an issue with the ABS block or it's electronics that interferes with the braking.

Are you able to get the car scanned for fault codes?

 

[rf065]

Is it diesel or petrol?

 

[StokerBlake]

I cannot explain it either, because the W203 has a traditional braking system, with a master cylinder and a vacuum servo unit, and so obviously it shouldn't be possible for it to behave like there's air in the system on some occasions and then be fine again.

The only thing I can think of is an issue with the ABS block or it's electronics that interferes with the braking.

Are you able to get the car scanned for fault codes?

Yes I have an icarsoft mb scanner I will look. The problem is repeatable so if nothing shows it may need star. It may be that the ABS does something only when in a driving gear. It is a petrol 1.8 litre kompressor. Thankyou for your reply.

 

[StokerBlake]

Is it diesel or petrol?

It is a petrol 1.8 litre kompressor. Thankyou for your reply.

 

[Bellow]

Yes I have an icarsoft mb scanner I will look. The problem is repeatable so if nothing shows it may need star. It may be that the ABS does something only when in a driving gear. It is a petrol 1.8 litre kompressor. Thankyou for your reply.

If it is electronic related, I'd be more inclined to suspect Hill Start Assist than ABS.