Im getting a lean run condition from bank 2.(dont remember the code number) My car is all stock. 49K miles. The light has turned itself off three times over the past two weeks. The light has come on three times also. Each time it came on it was a different situation. One will shifting into third under normal conditions, Once while in fifth gear cruising at 50, then once while idling in my driveway. I ran some techron injector cleaner through it after it came on the first time. I have also noticed a drop in MPG(bout 2 or 3 mpg) but this could be the weather change or me getting used to the car(just got it 2 months ago).

Anyone got any ideas?

 

I know my MPG drops 2-3 miles at least in the winter

 

There is no Bank 2, so I suppose that would be running VERY lean....LOL.

You only have a Bank 1, of which there are 2 sensors. Is it Bank 1 Sensor 2? or are you talking about P0172(?) Bank 2 Lean?

 

Ill have to make a run back by autozone and get it checked again and get the exact code.
Im sure he said bank two though. One more reason why i should have my own code reader....ARG!

 

Get an Interceptor Scan Gauge!!!!!!!!

 

The factory tune leaves a lot to be desired. We tuned my '06 yesterday and what a difference! I was getting a lean code every so often prior to us tuning it.



If you look closely at this dyno graph you can see that it is color coded. The colors up on the graph correspond with the colors at the bottom for engine torque , engine power , air fuel ratio and boost .
Number 1 at the bottom of the graph is the modified tune that we added in, and number 2 is the original tune. If you look at the minimum eng torque we really picked up a lot of power. This will make more of a difference than anything, and we may very well have improved the fuel efficiency as well. I'll let you know what I find out on the gas mileage.

I drove this Cobalt home tonight and the added torque made for a huge difference! This car pulls much harder than what it did before, and I noticed the car idles much better than what it did before. These cars are known for having an erratic idle from the factory, and it does not hunt around at all like it did before we tuned it. Bob

 

There is something wrong there, it should be 14.7 but i see 16AFR for the original, was that logged with an exhaust sniffer or an o2 sensor? There are decent gains i see and good AFR for WOT in the new tune, but i don't see the faster, lower commanded AFR allowing for improved fuel economy, unless you plan on accellerating WOT past 4000rpm on constant basis.

 

Wow, look at the torque difference just from the added fuel. Good job, and way to stay safe!

 

^^^holy massive siggy batman!

 

Exotic Performance P - "We tuned my '06 yesterday and what a difference! I was getting a lean code every so often prior to us tuning it."

The gm stage tunes run very rich, not lean. The code you were getting was more then likely a RICH code not a lean code.

 

It's not that they run rich on the top end, but they take too damn long to get rich. Look how long the tune spent lean.....that's normal for the GM Stage 2 tune too. And it's not good for power or for safety.

 

Agreed, however the stage 2 tunes run extremely rich on the top end. My stock stage 2 tune was running me into the low low 10s for my afr. That's way to rich. However yes, the stage 2 tune shouldn't take so long to richen up.

 

Haha, I had a P0171 pop up today while driving... turns out my intake piping (i have stock intake) came loose and was allowing in unmetered air, resulting in a lean condition.

 

got the code checked. P0171. Ill check my intake piping.
CEL oddly enough went away again today.
Could it just be the cold weather we have had recently(around 30ish most of the time)?
Dip stick is tight also.
Any other ideas?