Have been battling this problem for the last year.Changed o2's, map sensor,iac,cap and rotor,plugs and wires.I do have exhaust leaks on both sides but only the left bank is running rich.I have done searchs and read that the opti can possibly do this.I do not have any starting issues.The car runs perfect at WOT it only runs crappy at part throttle.I have done many Datamaster logs that's how I know its the left bank.Any help would be great.Thanks!

Rob.

 

Hey Rob,
Do your L BLM's show a lean (above128)
or rich(below 128) condition?
Kevin

 

Explain what data you used from DataMaster to reach your conclusion.

Are the exhaust leaks before or after the O2 sensors? Are they in the same place on both sides? Why don't you fix them and eliminate one possible source of the problem?

Do you have a crankcase breather?

 

Kevin the BLMs show below 128.Fred that is how I came to the conclusion.The BLMs dip down to 60 sometimes.I have exhaust leaks before the O2's on both sides that's why I don't think it is from the exhaust leaks.Wouldn't I be running rich on both banks if that was the case. And yes I have a crankcase breather on the passenger side valve cover.Thanks!

Rob.

 

Can anyone help me here?

Rob.

 

Fix the exhaust leak, then see if it still does it, till then the BLMs are about meaningless.

 

It isn't possible for the long term corrections (BLM's) to go below 108. Are you sure yours went to 60? Or is it possible you were looking at the short terms (INT's)?

I just had a data log from someone who claimed he traced his "split" BLM's to the breather. Not sure why, but his data sure supported his conclusion.

An exhaust leak causes a "false" lean, and drives the BLM's above 128. You would get a "false" rich from a leaking injector... the excess fuel combines with the residual O2 in the exhaust, and fools the sensor into thinking the mixture is rich... the PCM reduces the BLM's.

Not sure why you would continue to drive around with exhaust leaks.... may not be causing the problem, but it may be complicating the problem and making it harder to solve.

 

Fred I am not driving the car just trying to solve my problem to head back to the track.I have some earl's graphite seal header gaskets on order.I have I daily driver the Camaro is a toy (weekend Race car).The breather is on the passenger side.The drivers side is running rich.The problem is at part throttle when I get on it it runs great.Seems to running crappy after a couple minutes of driving it.

Rob.