I have a '92 300te 4matic which has two problems

1.It is slow to start when cold.
It will take mutliple tries (it does turn over strong-new battery) before starting and then it will be very weak with rough idle. If i step on he gas it dies but if i leave it alone,it will slowly idle more normally with time- but 30seconds.
I have changed the cold start valve and a cracked distributor cap.
When it is warm i dont have this problem although the idling then is still a bit rough/unsteady.
beyond this the car drives normally, round town and highway.

2.The other problem is a grinding/shaking sensation when the brakes are applied firmly/quickly at highway speeds. This sensation I think is coming from the right front end.
Have install new brake pads/rotor but the problem persist.

Any ideas? please help

1. Best thing to do is check the fuel system for abnormal pressure leak down. Common contributor to such problems is a bad fuel pump check valve.

2. My guess is warped brake rotors.

Sixto
91 300SE
87 300SDL
83 300SD

For the hard start, I think you need a new set of spark plugs, if you you have some evidence of wear and tear on the wires then replace them otherwise.
For shaking idle and hesitation check engine temperature sensor that specifially reports to the fuel injection loop only.

thanks, will check out your suggestions.
On 2. The brake rotors and pads are new. any other ideas?