Re: Check Engine Light
A vacuum leak at the intake will cause a lean code. Do you hear a hissing noise from the engine??? Check fuel pressure. Also using a scan tool watch the upstream O2 sensor switching between rich and lean. It should be continually switching between rich-center-lean. If it stays lean then try a new O2 sensor. Might as well do the other upstream while you're at it, because their probably both aged. The downstream ones normally only come into play for the catalytic converters.
Master ASE Certified L1 Chrysler Technician- still a Ford fan at heart.
1964 Thunderbird Hardtop- Chantily Beige- 390 FE 4V V8-Uncle's Car
1966 Thunderbird Convertible- Red- 390 FE 4V V8- Uncle's other car- waiting for paint and body work!!!