Yes, I did put a bottle of fuel injector cleaner but didn't help. Fuel filter and regulator both checked OK. There seems to be a burnt smell though not as bad before the oxygen sensor was replaced. Duran is a 2 man operation and has 6 other cars with sure fire fixes to work on. He can't give me definite answers. Thanks for all your help people. I didn't realize there is a wide universe of MB enthusiasts out there. This is becoming a challenge but I'll get it fixed and will get back with the fix. By the way, if anyone is interested the car is for sale for $9.5k. Parts and labor spent since 5k ago total almost $7k. You can email me at email@example.com
if interested and I'll email full info and pics. Roland 214-684-6857.