Digital Disaster

My car has started regularly setting "lean condition" codes - always right and left bank at the same time. The codes only set at idle, and with or without codes, the car runs smooth and strong.

After a little research I found that this is usually caused by a dirty MAF so I carefully cleaned mine and was able to take one weekend drive without a code. On the next weekend drive it set again while idling at a light in closed loop.

This car has 20K miles, and all vacuum lines, etc. look like new.

Any ideas? I'm thinking maybe fuel filter?

pcolt94

I would tend to start with a scanner and looking at the O2 readings. See if they swing properly. I would also look at the BLM numbers and look at long and short fuel trim. If all that looks good, than you might have to keep checking around as you are doing now. Check wiring connections and those kind of things. Or the PCM just might be throwing out false codes.

**I also remember reading about intermittent EGR problems causing sporadic codes also. Check out the EGR valve itself as well as the solenoid.

Digital Disaster

Thanks pcolt94, I'll check out those things

JAKE

On the one occasion I had a lean code on my 86 TPI I traced it to a failed 02.

Jake

WW7

You really need to hook up to a scanner to see whats going on...WW

JAKE

Yep, that's how I found my cause.

Jake

WW7

For a car to set a lean code the car has to be very lean, the Blm has to be above 140 to set a code..The normal setting would be 128. If this code is real, running the car this lean could do damage over time.I would scan it soon and check both the (Block Learn) and the (integrator) for readings, both should be around 128..It could very likly be one of the 02 sensors , these are suppose to be changed as per the FSM...WW

Digital Disaster

The reason why I have a hard time thinking it's an O2 sensor is because it sets both right and left bank lean condition codes simultaneously.