Hi everyone, I'm a new member here, but a long time Ford owner.

I have a F-250 V10 4x4. I'm looking to change out my O2 sensors (upper ones on Y pipe) and am having problems trying to disconnect the electrical connection on the sensor on the passenger side. My arm and hand just isn't long enough to grasp it to loosen the connector from the underneath. The connector is at the rear of the engine so I can't even reach it from the top down. I'm thinking to get to it I probably need to jack it up - it's kind of lifted already because I can easily get under it without any jacks - remove the fenderskirt, front tire and then reach in that way. I have side steps on the truck so if I choose the skirt removal option I will need to remove the step also, because the two of the bolts that hold the skirt on are just right there in that magic spot between the body, step and the fenderskirt.

Is this the best way to do this? Also, because I can't really see either sensor it's difficult to see how it clips into the harness. Does anyone have a picture of the clip - I purchased O2 sensors from Schucks here locally - about $50 less than dealer charges here in Boise but it's just kind of difficult to tell how it goes together. I'm sure after I get the first one - driver side (aka bank 1 I beleive since cylinder one is the driver side) - this one will be easy if I can just reach it.

Additional info on the rig: There is about 85K miles on the vehicle and I'm trying to do a really good tune up on the rig - I do mostly towing with the vehicle; I normally tow about 11,500 lbs up and down mountains in the northwest. I'm also in the process of swapping my 3.73 to 4.3 on the rear differential, currently running 235s on the tires. I realize this doesn't have anything to do with the O2 sensors, but the purpose of the tune up is to help with towing.

Thanks in advance, love the forum, lots of great information here.

 

The harness is the same on both sides, so if your doing both, it will be identical to the drivers side. Mine was pretty easy, so I am not sure how to tell you how to do it. However, the inner fender wells can be loosened enough to get between and behind them. You might want to try loosening some screws/bolts/retainers first to see if you can get at the plug.

If your replacing them, you can cut the pig tail, remove the sensor and unplug it once the sensor is out of the way.

 

I recently replaced the O2 sensors on my '99F250. Yes, the passenger side elec. connector is way up in there. Luckily my long arms were able to reach the connector. After replacing both sensors, I gained about a half MPG and also noticed the engine running a little smoother.