explorer running rich

[LukeDog3D]

My explorer is running rich and is surging while idling. I changed the oxygen sensor and forgot to reset the computer. I ran the truck for about 10 minutes, then reset the computer properly. The truck still runs rich and surges while idling. I also cleaned the mass air flow sensor, which wasn't very dirty when I looked at it. I have been suggested to inspect EGR valve? and fuel pressure regulator?.

 

[CADDYBILL]

running rich

Did you check to make sure all of your wires are properly conected ? The last time I checked my are cleaner, I left one of the wires going to the top of the air cleaner disconected and had the same symptoms you described.

Caddybill

 

[LukeDog3D]

yea i checked all the electrical connections and vac hoses, couldn't find anything that was loose. Could the sensor have been fouled while running w/out being reset?- also, i forgot to mention that i brought the truck to a shop and had it connected to a diagnostic scanner, which read that the o2 sensor was bad. This was before i changed it btw. thanks for the reply caddybill
later

 

[Brian1]

So you already replaced the O2 sensor? I would have thought that it would fix the rich problem but surging idle it might be something with the fuel system.

 

[ammo troop]

Had the same problem you described...well somewhat, Look into your cooling system, something as minor as a thermostat sticking open will tell the computer your truck is not warmed up and therefore your are always running in a choke mode, as far as the surging, I found that the extra fuel contaminated my o2 sensors and spark plugs causing my surging. Aren't computer controlled vehicles fun? Anyway hope this can help you out...