mileage sudden drop on 1999 Mercury Mountaineer

check engine light on and code indicates lean burn. Sudden drop in mileage per gallon from 15 to 10. what could the problem be. The mechanics here are baffled.

by in Allison Park, PA on June 25, 2009
1 answer
ANSWER by on June 26, 2009
Can you post the codes that are being stored in the engine control module?