Notices

O2 sensor install questions

Thread Tools
 
Search this Thread
 
Old Dec 17, 2007 | 11:55 AM
  #1  
earlybirds's Avatar
earlybirds
Thread Starter
|
Senior User
Joined: Sep 2006
Posts: 107
Likes: 0
O2 sensor install questions

'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!
 
Reply
Old Dec 17, 2007 | 12:17 PM
  #2  
Hootbro's Avatar
Hootbro
Tuned
Joined: Apr 2005
Posts: 396
Likes: 2
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
 
Reply
Old Dec 17, 2007 | 12:57 PM
  #3  
galaxie641's Avatar
galaxie641
Postmaster
Joined: Nov 2006
Posts: 4,517
Likes: 3
From: SE Wyoming
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.
 
Reply
Old Dec 17, 2007 | 08:28 PM
  #4  
2000BLK54's Avatar
2000BLK54
Tuned
20 Year Member
Joined: Sep 2003
Posts: 311
Likes: 3
From: Arkansas
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.
 
Reply
Old Dec 27, 2007 | 10:24 PM
  #5  
royb's Avatar
royb
Senior User
Joined: Dec 2007
Posts: 162
Likes: 0
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.
 
Reply




All times are GMT -5. The time now is 04:52 AM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE