CHARLIE B

My S 420 started idling a little rough and occasionaly stalls at idle in gear check engine light is on when checked it indicated an air intake problem. The check engine light would go out for a while then go back on. I checked the air filters ,new, and added some injector cleaner which seemed to smooth it out alittle,but it still idles rough at times. Car accelerates and runs fine at speed.

Any help would greatly be appreciated thanks Charlie , Massapequa N.Y.

lboudreau

O2 Sensor?

You might find more help from this part of the forum: https://mbworld.org/forums/s-class-w140-29/

CHARLIE B

Thanks for the reply . I changed the )2 sensors a while back the read out reflected anair intake problem could it be a bad idle injector?