So what exactly does a smog pump do? mine seems to have been bypassed, carlos of mr.mb says its no big.

What year & model car??

All 1980 & later MB's use the air injection system as a catalyst warm-up device.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

1993 300ce, that explains why the car stinks so much... probably needs a cat too

I'd like to remove mine,I have no cats

__________________
1999 w140, did it my way, next life hopefully south america