1993 Buick Century

1993 BUICK CENTURY
192,000 MILES • 6 CYL • FWD • AUTOMATIC
Avatar
PETEPROBINSON
  • MEMBER
  • 1 POST
1993 Buick Century Custom 3.3L
Car runs rich, smells at tail pipe, ruff at idle; fuel mileage is at about 10MPG
Check engine light is not on but does work. Runs the same hot or cold.

1. New o2 Sensor
2. New Mass Air Sensor
3. New Engine Control Computer (used old PROM did not buy new one)
4. Shop performed BG injection cleaning

Fuel pump is relatively new.
Good plugs and wires
Checked all fuses.

Sick of throwing parts at this car.
Lost!
Jun 15, 2009 at 1:54 PM
Advertisement
Avatar
RASMATAZ
  • CAR REPAIR CONTRIBUTOR
  • 75,992 POSTS
Typical symptoms of an engine that is running rich (too much fuel, not enough air) are poor fuel economy, elevated emissions (Carbon monoxide or CO), and engine may have rough idle or surge condition.

Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.
Jun 15, 2009 at 3:09 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.