I purchased a 1985 280SL with 40K original miles. never driven in inclement weather and was pampered by the original owner.

I have replaced the entire exhaust system with stainless steel from Time Valve. This included a new Bosch "co" sensor in an attempt to pass the DOT emission test.
The engine passes the HIGH end test (2500-rpm) with no problem. However it will not pass the LOW end . The HC reads 257 and the CO reads 2.42 at idle.
The car is HARD TO START when it has been driven to operating temperature, then shut down and an attempt to restart is made after setting for 20 minutes or more. It starts immediately if the engine is cold!
It appears that the engine is flooded with raw fuel as a couple of cylinders start fireing, then the others start coming to life. Once it is running, it runs and idles perfectly! If the hot engine is shut down, then restarted immediately, it does not load up.
I would appreciate any help. Since the car is a euro, my MBZ dealer says he has no mechanics that are familiar with this twin-cam 110-990 engine. They are willing to work on it, but they will be on a fishing trip at $80.00 per hour.
g/f