Failed Smog In Mercedes Please Help?

B

BrianJ

Member
HC[PPM] CO% RESULTS



15MPH MAX GP MEAS MAX GP MEAS GROSS POLLUTER

81 265 201 0.47 1.97 2.56



25MPH HC[PPM] CO%



MAX GP MEAS MAX GP MEAS FAILED

46 215 186 0.44 1.94 1.83







ITS MY MOMS MERCEDES 1995 E320

JUST HAD NEW 02 SENSORS AND CAT

ANY SUGGESTIONS?
no it is gas
has 245k miles
always uses premium chevron and thats it
very well maintained
thank you for responses
 
R

RickyJe

New member
Yes. Look for vaccum leaks, including the oil and fuel caps.
First check all of the hoses. You can do this by geting a can of starting fluid and shooting a little bit at each of the hose ends. If the motor speeds up, you know that's a leak point. Trim a quarter inch off of the end and stick it back on.
Next make sure that the compression is good and the plugs are new.
After that flush the fuel system, replace the fuel and air filters, then swap out to a much heavier grade of oil to get the compression back up to snuff.
Above that make sure that you're using the absolute highest quality fuel you can find.
Last, make sure the motor is hot when you get there. Meaning that you get hot air when you turn on the heater. (even a brand new motor with zero miles wil fail if tested when still cold).
That ought to get you through.
 
Top