Good point, David.
I figured after almost 120k the Oxygen sensor was probably past due anyways and will try that before I go any further.
The "check engine"-light is , to my knowledge, exclusive to California cars. Mine is originally a N.J.-car and thus doesn't have it. Too bad, I got used to it, driving mostly California-version cars.
Thanks a lot for your thoughts.
81 300 SD grey/palomino 168K miles
84 190E 2.3 black/grey 64K miles (wrecked)
85 190E 2.3 maroon/palomino 92K miles
88 300E desert red/palomino 204k miles
(made to look like a '94-95)
92 400E desert taupe/creme beige 120K miles
(converted to 94-95 E420 looks)