Bank 2 lean?

RIDE-IT said:

ive been having problems with my SES light coming on lately. ive had it scanned at autozone, and it said system lean (bank 2). i just replaced my old o2 sims thinking they were bad after a year of driving them in the rain and salty conditions here in ohio, but the code still keeps coming on after resetting my computer. could this mean that one of my o2 sensors are bad or could it be something else like, my c&l plenum or mass air making it read lean? please help!

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Do you have mil elimators for your x-pipe? If yes what kind.

If you have unmetered air getting into the system you will throw the SES light and get lean codes.

Be sure all connections after the MAF are tight and move down the list of possibilites..

I had a lean condition when my I had MAF rotated with the plug towards the passenger fender. After I moved it back with the plug on top, I cleared the code and it hasn't shown yet. I have a bend before my MAF with a cai going into the fenderwell. If I rotated it with the plug towards the engine then it had a flatspot in it. something to try.

Mil Eliminators cannot cause a lean code. Those codes are associated with the front O2 sensors. And since its a lean code and not an O2 sensor error code it more than likely is an actual lean condition. Since its only one bank (bank 2 is drivers side) and not both I would start by looking for an exhaust leak ahead of the front O2 sensor. That would be at the head/manifold point or the manifold/downpipe point. If you cant find something there then move to the intake side. And yes an MAF can cause a lean condition if its not properly metering the air flow.

Bank 2 is the driver's side and getting a lean code for just that side implys that there is a problem with either the forward O2 sensor (driver's side) or fuel starvation on that side (possibly a clogged injector). Any vacuum leaks should affect both sides, but it may be on the verge of doing that. If you don't have the means to monitor your fuel injector pulse width, fuel pressure, and O2 sensor outputs, the easiest way to deal with this is to swap the forward O2 sensors to the other side. Clear the codes and see if it shows up again. If the problem moves to bank 1 replace the O2 sensor. If not, test the injectors on the driver's side and look for vacuum leaks on that side. Autotap comes in real handy if you have access to one to diagnose this problem.

Good call on the injectors Sam. A clogged injector can most definately do this. And yes, a quick look at the long term fuel trims will tell you whether its on the intake side (which would affect both banks) or from one bank onward. If one trim is "reasonable" and the other is pegged lean (which is what causes the lean code) then its gotta be primarily in only one bank. If both trims are way lean then its an air metering issue which includes intake leaks.