Bad Oxygen Sensor?

[vsman77]

Would a bad oxygen sensor cause the engine to run bad sometimes? My van could pull good 1 minute and bad the next.

Vaughn

[vsman77]

I wonder if my computer is retarding timing once in a while because of my oxygen sensor?

Vaughn

[xrattiracer]

most likely not the problem, the o2 sensor only effects things when the engine is not under a severe load. best way to tell tho is to just unplug it for awhile.

[glhsken]

No, don't unplug the sensor, the car ADDS tons of fuel to make sure it doesn't run lean. Check your codes. That wilkl tell you if the sensor is having issues

[vsman77]

The last time I checked, there were no codes. But I will check again. Also when driving on the highway, if I floor it, it goes. But when I let off to about half throttle, seems like it pulls better. Is this normal?

Vaughn

[glhsken]

Yes, It's normal, but the engine is going lean and it's a risk to the pistons. At WOT, the car "richens" up the mixture.

[vsman77]

What will be causing my engine to go lean? The only mod I have is a K&N filter and RN11YC plugs.