I'm getting a DTC 64 on my Scanmaster. Looks like I have a lean bank 2. There are no real exhaust leaks that I can see/hear. What else is going to cause this lean code? Vacuum leak? LT1 gurus I need your help. The car also idles at about 550-600rpm when I have my idle set at 900. Is this a symptom of the lean problem?

 

Possibly a vacuum leak, wouldn't hurt to check all the hoses. What are your other scanmaster readings?

Might be the wires, the sensor itself or low fuel pressure. Take a look at the wires, make sure nothing is damaged or stretched etc (do you have extensions?) You could swap O2's and see if the problem follows the O2.

 

Look at your long term fuel corrections for various cells. That will tell you if you have a problem only on Bank 2, or if there is a problem on both sides. If you have elevated BLM's on both sides, its a problem that is common to both banks (e.g. low fuel pressure, faulty MAF readings, vacuum leak affecting the entire intake system). You may have the lean code only for Bank 2, but Bank 1 may be not quite close enought to set off DTC 44.

If the problem is only causing elvated BLM's on Bank 2, and Bank 1 is normal, then you will know you have to find something that is only affecting the right bank of the engine - e.g. misfires, faulty O2 sensor, faulty wiring harness, etc. By not listing the mods on your car in your signature, you really limit the amount of help people can give you.

Vacuum leaks will generally cause the idle to elevate, not drop.