My 2001 Lightning check engine fault code say banks 1 & 2 Lean? I have replaced the mass air sensor and all four Oxygen sensors and the check engine light reappears after about 50-60 miles. it occasionally idols slightly ruff! any ideas? I suspect the auto choke.

 

Vacuum leak.

 

Yep, common vacuum leak.

 

I have been unable to find a vacuum leak. I have tightened all the fitting between the air box and the intake. any suggestions?

 

Check the PCV system from the valve back to the intake.

 

Two hoses between back of engine and firewall. Very prone to rot and leaking. Go to Lightning Rodder and search.

Jim

 

turkey pan line rotted out most likely