O2 sensor install questions

[earlybirds]

'99 5.4 V8 Superduty regular cab
I originally posted these questions in the Superduty forum, but got very little response. Truck has 103,000 miles on it, so it is probably past time to change the O2 sensors. There are only 2 O2 sensors upstream of the cat convertor. Driver's side sensor looks easy enough to access for replacement. Passenger side sensor looks a lot more difficult. The electrical connector is WAY up on the backside of the engine and is not accessible from the topside. I can barely touch the connector laying on a creeper under the truck. Any tips or tricks for replacing O2 sensors?

Question #2: Do I need to disconnect the battery before replacing the sensors or after replacing them to "reset" the truck's PCM? Does the battery need to be disconnected at all?

Thanks in advance for any advice. You guys rock!

[Hootbro]

Question #2: Do I need to disconnect the battery before replacing the sensors or after replacing them to "reset" the truck's PCM? Does the battery need to be disconnected at all?

No need to disconnect the battery during change out. I would pull the fuse for the PCM for 30-60 seconds to reset it. This will allow the PCM to "relearn" your driving habits based on better O2 sensor values.


Hootbro

[galaxie641]

I gave up on trying to disconnect mine and took it into the shop. Who ever designed the plug locations should be shot. My guess is when it is on a lift and you are standing up it is far easier to get your hand up there. Even if you can get a hand on them they have that stupid prong connector that is near impossible to remove with one hand.

[2000BLK54]

Get the O2 sensor wrench that uses a 3/8" drive ratchet offset from the socket's body. OEM brand tools makes one and you can find them an Autozone. They are much more compact and can be better indexed to get a good grip on that O2 sensor. If this picture doesn't post then follow the link.





Try to be sudden when breaking these things loose, too slow and you'll strip the sensor and you'll really have a problem. Soak with a good penetrating oil (Aerokroil, PB, etc..) for a good 30 minutes before starting on it too.

[royb]

Originally Posted by earlybirds

'99 5.4 V8 Superduty regular cab
I originally posted these questions in the Superduty forum, but got very little response. Truck has 103,000 miles on it, so it is probably past time to change the O2 sensors. There are only 2 O2 sensors upstream of the cat convertor. Driver's side sensor looks easy enough to access for replacement. Passenger side sensor looks a lot more difficult. The electrical connector is WAY up on the backside of the engine and is not accessible from the topside. I can barely touch the connector laying on a creeper under the truck. Any tips or tricks for replacing O2 sensors?

Question #2: Do I need to disconnect the battery before replacing the sensors or after replacing them to "reset" the truck's PCM? Does the battery need to be disconnected at all?

Thanks in advance for any advice. You guys rock!

an o2 sensor can last the life of the truck/car. why replace unless you get a code that says they wont heat up. also use oem brand the aftermarket tend not to last nearly as long. on your question 1. I've cut a wrench in half to mak eit easy to get in tight spaces . #2. no need to disconnect battery. make sure car is not hot & use anti sieze on thread.