Strange AFR Behavior

[jrho]

I tried searching last night but couldn't really find anything helpful.

 

Starting yesterday after work. I noticed my AFR to be consistently around 14.7 whenever I was on the throttle. This would be the case regardless of whether I was cruising at the steady speed or accelerating at part throttle. The AFR would change when I would let of the gas (go to 20.XX as per usual), but then if I would go back onto the gas it would barely dip below 14.7. Car isn't throwing any engine codes and it doesn't seem to be hesitating at all so I'm super confused. Any insight would be greatly appreciated as this is freaking me out

[relative4]

Sounds good. What were you expecting to see? What are you seeing at idle?

[ehsnils]

14.7 seems to be pretty normal and when you let off the throttle then it cuts the fuel feed because there's no point in feeding any fuel to the engine then.

[jrho]

I have no issues with it at idle it's just that during driving it's always near 14.7. It will usually richen up with load or on boost but it doesn't seem to be doing that which has me freaked out

[ehsnils]

It depends on if it's in open loop or closed loop. In open loop it may get richer, but it also depends on factors like fuel quality, air pressure, air humidity, air temperature, engine temperature, air filter condition, if the MAF is dirty, the condition of the MAP and throttle position sensor.

 

With fuel quality I primarily think of to how high percentage of ethanol that's mixed into the fuel.

 

But how do you detect the AFR? Separate gauge/sensor?

 

If it's in closed loop then the O2 sensor sets the target of 14.7.

[jrho]

It depends on if it's in open loop or closed loop. In open loop it may get richer, but it also depends on factors like fuel quality, air pressure, air humidity, air temperature, engine temperature, air filter condition, if the MAF is dirty, the condition of the MAP and throttle position sensor.

 

With fuel quality I primarily think of to how high percentage of ethanol that's mixed into the fuel.

 

But how do you detect the AFR? Separate gauge/sensor?

 

If it's in closed loop then the O2 sensor sets the target of 14.7.

 

Yeah it seems it's running constantly in closed loop. I'm detecting AFR through my Accessport which I know probably isn't the best way but it's never done that before. I'll check the things that you mentioned. Living in a small oil and gas town, it's been super dusty lately. Thanks!