how hard is it to replace the front 2 o2 sensors on a 97

 

Its not the easiest thing, but its doable. Its just a matter of getting the tools in there, its not complicated at all.

I borrowed the 02 sensor removal tools from Autozone and that made the drivers sensor a snap. The passenger side sensor took quite a bit of work...I recommend that you have a variety of tools that will fit a 7/8" nut. Probably the most helpful was the open end wrench.

I actually had to loosen/partially remove the tranny dipstick tube, but it seems nobody else had that much trouble that I have seen...I also removed the front pass. side tire, made it a little easier to work under there.

Also, if you have one of the smaller engines it might be a little easier.

 

i had someone tell me today not to replace my 02 sensors unless the check light came on. should i replace them anyways im only getting around 12mgh

 

Ox sensors are made with porus material so exhaust gasses can enter and generate an output in relation to the amount oxygen left after combustion.
Additives in the gas and unburnt carbon begin to plugup the porus material and start making the response time slower and slower as time goes by.
It is always good to replace them after about 40,000 or when fuel milage begins to go down and not to wait until a CEL lamp comes on with a code that points to them.
Also their switching time is part of the testing the PCM does to evaluate the cat converters for their operating efficiency.

 

thanks bluegrass,
ill be putting my new ones on tomorrow

 

The front "upstream" sensors take about ten minutes apiece, tops. One 22mm wrench is ALL you need. Clear goggles are preferable because all the debris will fall in your eyes when you're laying under the truck. You don't need to remove wheels or anything else.

WARNING: If you drove your truck 1-2 hours before working on it, the catalytic convertors and other pipes and things will be warm or even hot - don't burn your face. BUT: Even with them hot you can lay underneath and not burn yourself if you're careful (if you absolutely can't wait two hours). Both sensors are very, very easy to reach. It's the rear "downstream" ones that are a little harder.

 

...if you have to remove half of your truck in order to remove the upstream oxygen sensors, you are either not working on a F150 4.6L V8 (or 5.4 if it's similar), OR.... you're doing some wrong, OR.. you have abnormally large hands...

These sensors are the same as typical packaging, in that it's meant to be opened really easily.. if you have to tear through all the plastic instead of snapping off the ziplock thing, you're not doing it how it's meant to be done.

 

Where were you when I changed them on my truck???

As a side note, if my wrenches were a different length I might be singing a different song. Everytime I tried to get it up there something was blocking the way...there wasnt really any other way around it for me.

 

If your changing the O2 on a 4.2 the best thing to do is take of the front tires. Soak the sensors VARY wall with a penatrating oil (Zep penatrating oil seems to be the best) than going at the sensors from the wheel wells cut the wires directly above the top of the o2 sensor and remove the harness and use the box end of a 7/8 to brake the sensors loose. than if you are using Universal O2 simply splice them in and replace, if you are using OE just replace. I work for an auto shop and we discoverd this is the easest way.

 

the trucks a 5.4 and it was easy to do. just got to have the right kind of tools i guess thanks for the help