I have a 1993 300E w/ 120,000 miles. Recently I have a problem when the car is accelerating. If I accelerate hard (mash the pedal) the car sputters and coughs then eventually smooths out. This happens from a standing start or while at speed. I have replaced the Mass air a month ago but it did not fix (different issue it fixed). We have local emissions testing for pollution control, car passed emission testing no problem, so it would seem it is not an emission related part (O2 sensor, Nox, etc.) My mercedes specialists are not sure what to do, beyond replacing parts till it is fixed. (not a MB dealer, mercades trained mechs who opened their own shop) What they can not check is the computer(chip), My dad owned car previously and had troubles 3 years ago getting emission test passed. Dealer had car for three days and replaces, fuel presure ? valve? and it passed. My Dad say's it always ran lean after that.

Any ideas? Oh car runs better when cold (first thing in morning, but only then) then problem persists throughout the day.

 

what is your engine number?

better if have vin

 

2.8 liter, 104.942 engine (as I understand it)

vin# WDBEA28E7PB886443

 

seems your car is non-catalyst.

please check the refference resistor if it is 2,400 ohms (R16/2). if not, replace it.

find the variable resistor where you can adjust the CO manualy. the mechanic must have lean it out. tighten it for about 4 complte turns and observe. do not overdo for it might get too rich. REMEMBER your turns so you can go back for emission check in the future.

VIN WDB1240281B886443
Model 280 E
Chassis 1240281B886443
Engine 104942 12 005018
Transmission 722433 03 273987
Order 0 2 705 91063
Approx. year 1992
Lights BOSCH
Wiper BOSCH
Cab 03792
Dealer United States (USA) (705)
Interior mb-tex mushroom (175)
Paint
485 rosewood metallic (ั 01.01.1992 ะฟะพ 31.12.1995)
75 Unknown code
Options
221 left front seat, electrically adjustable (ั 01.11.1978)
222 right front seat, electrically adjustable (ั 01.11.1978)
240 outside temperature indicator (ั 01.03.1982)
280 steering wheel (400 mm dia.) and gearshift lever in leather trim; on W202 390 mm dia. (ั 01.05.1984)
291 airbag for front passenger
airbag for driver and front passenger (ั 01.07.1987 ะฟะพ 30.09.1993)
airbag for driver and front passenger (if driver airbag standard - then only for passenger)
300 storage box in front tray (ั 01.05.1988)
340 additional 3rd stop lamp (ั 01.10.1989)
412 electric sliding roof with tilting device (ั 01.07.1983)
420 automatic transmission, floor shift (ั 01.01.1963)
430 headrests in the rear (ั 01.01.1977)
440 tempomat (cruise control) (ั 01.09.1975)
461 instrument with mileage reading and english lettering (ั 01.04.1990)
491 USA version (ั 01.01.1963)
524 paintcoat preservation (ั 01.01.1964)
543 sun visor with vanity mirror, illuminated, left and right (ั 01.11.1978)
551 anti-theft warning system (ั 01.11.1978 ะฟะพ 31.03.1998)
588 automatic climate control and electric window lifters (front and rear doors) (ั 01.01.1977)
593 heat-insulating glass, all-around, heated rear window pane (single-sheet safety glass), band filter
green heat-insulating glass all round, heated rear window, single pane safety glass - tinted strip (ั 01.01.1972)
611 courtesy lamps for front and rear doors, with W124 also for central doors/W202 front doors only (ั 01.11.1978)
639 elimination of first-aid box and warning triangle (ั 01.08.1977)
640 15-hole light alloy rims (ั 01.01.1990)
664 10 liters of fuel and mode of packing VE III (ั 01.01.1979 ะฟะพ 30.06.1993)
757 Becker radio Grand Prix 2000 - USA (ั 01.06.1990 ะฟะพ 31.03.1994)
803 Change of year of model, last figure shows new model year
814 active bass loudspeaker system (ั 01.10.1989)
916 Unknown code

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