Lean On It

1 own a '00 Celica with basic bolt-ons that include an intake, header, and exhaust. The car has 125,000 miles and has been flashing a lean "cylinder bank #1" check-engine light (CEL). My friends and I sprayed soapy water around the engine while running to see if there's a vacuum leak, but the results were inconclusive. The engine doesn't stall, but I'm beginning to suspect the problem lies with a faulty

02 sensor or a bad catalytic converter. I figured I would ask the pros before buying any replacement parts I might not need.

-Ahmad Carter Duluth, GA

The first thing to do is check the engine's compression with a compression tester. While the spark plugs are out, you should also check your plugs and make sure they are all a similar color. You say you're getting a "cylinder bank #1" code, but there's only one bank on an inline-four engine. If it does really say "bank ft1" then it is likely the short-term and/or long-term fuel corrections are beyond the ECU'S ability to correct. You can view these OBDII parameters in real-time if you have a capable scanner. This could be because of the modifications you made to the car, or a bad oxygen sensor, bad MAF sensor, or other mechanical issues like a collapsed catalytic converter or a vacuum leak. Unfortunately, there's no way to correctly diagnose the car via email, so I would recommend you take it to a knowledgeable mechanic for a proper diagnosis.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

Get My Free Ebook


Post a comment