My check engine light kept coming on, so I finally brought it in and had the code read. The dealership said it was the oxygen sensor and must be replaced at a cost of $260.00. Question, what does it do and must it be replaced,also is this a job a average owner can do? This is for my 97 lariat2x4 5.4 engine. All advise will be appreciated.

 

I'm no mechanical expert but I would think you could replace them yourself. I had them replaced under warranty on my old 4.2 V6 and the sensor were about $43 a piece. Total was 2 sensor at $43($86) and .5 hours of labor($31). With all there testing and cumputer hook ups etc. it only cost Ford $183. I would look into doing it yourself. The sensors are located on the back of the headers I believe. You'll se a wire going to them. If you attempt it make sure you put anti-seize on the threads.

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Red '97 F-150 SC 4x4 off-road, 16" rims instead of factory 17"'s(borrowed from old '97 reg cab), BFG 265/75 16 all terrain T/A, K&N filter with modified air box, Flowmaster 40 with duals out back, Expedition center console, 3" rear seat lift, after market stereo seen at HTTP://members.sounddomain.com/red97,

 

par
red97 is right, they are easy to change. The bad news is there are 4 ego sensors on these things & unless they told you which one, it'll be a guess. The passenger side front seems to be the first to go bad. My dealer changed mine at 35k. I changed the driver side front at 57k. I also have a code scanner that tells you which one.

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97 Lariet-sc-4.6-4x off road-auto-3.55 LS-
superchip-K&N-3"
pvc air box mod-Granetelli MAF

 

What error code were you getting with that?

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97 F-150 S/C 4x4 ORP XLT 4.6 K&N , Flowmaster w/dual tailpipes, Bosch+4 plugs,Ford 9mm wires,Superchip.Patriot fiberglass toneau cover, Westin chrome step bars. Rear seat lift 4".
Kenwood 4011 stereo, USAcoustics 2150 amp, Profile electronic 3 way crossover, 2 10" IDQ DVC's, and Polk Dx7 5x7/6x8 3 ways in the front doors.

FUTURE PERFORMANCE MODS:
4.10 gears, Edlebrock shocks, Magnacharger, Airaid, and slotted rotors.

OTHER FUTURE MODS:
Ram Air hood w/functional ram air, suspension lift, 17" polished wheels, 35" tires, and sunroof.

 

p0150 to p0155 for drive side--p0130 to p0135 for pass. side.

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97 Lariet-sc-4.6-4x off road-auto-3.55 LS-
superchip-K&N-3"
pvc air box mod-Granetelli MAF

 

My light went on yesterday. I stopped at Autozone today and the reading was P0155. I'm at 35k so I have an appointment at Ford for Wednesday.

I was a bit concerned becasue checking the code cleared the light. I was not sure if the code would still be in there when I took it in to the dealer. By the time I got home the light was on again.

 

I would say, as this comes from asking Mike Toyer (Superchips guy) that it is usually the two front ones ahead of the cat’s that go bad due to high heat. I would only replace them two first. If you replace them yourself there is a special tool you can buy (not sure where) so you can remove them and put them on without damaging the connector in top of the sensor.

They screw in and have a connector on top of them that plug in and give the computer an input on the state of the exhaust system, such as oxygen etc. That in turn cause the engine to run more lean or more rich. If they are going bad, and my understanding is correct it will cause your engine to run more rich, so yes they MUST be replaced if not working correctly.

Very IMPORTANT if you put new ones in add the anti-seize compound to the threads, and DO NOT cause any damage to the connecter on the oxygen sensors or you will have to buy new ones. That is not to scare you away from doing it because it is not impossible, only to make you aware of it.

Another important thing that will make them much easier to remove is to remove them when the exhaust system is hot or warm. In other words if the truck has been sitting let it run for 13 – 15 minutes or so. Since the exhaust system will be hot be careful not to burn yourself. You don’t have to put the new ones in while the exhaust is hot. When removing the old ones you won’t have to worry about damaging the old sensors connector, just don’t hurt the plug and don’t break it trying to take it off. Might be better to unplug it first before you start it up so you don’t have to mess with it while it is hot under there.

Hope that helps…

 

Thanks for the detal 01. I'm still under warranty so I'll have the dealer change it. I'll be looking for this message when the other one goes.

I wonder if I caused it to go by driving hard. I was late for a basketball game and I'm the coach, so I was on the gas real hard, which I don't do very often.

I was en route to the wrong school, so I exited the freeway and got back on in the other direction. That's when the light came on.

 

romping on the gas didnt hurt your 02 sensor. You can buy an 02 socket wrench at pep boys, oreileys,autozone type places. Paid about $10 for mine. Front sensors (closest to the engine) are more likely to go out first. However, computer codes are notorious for reading what appears to be an 02 sensor fault when in fact something else is causing the engine to run lean (more often lean than rich). If ford dealer said sensor was bad i would tend to agree with them. (i do all my own maintenance but there are a bunch of very competent mechanics in most dealership shops and i think twice before assuming an incorrect diagnosis). If a code read at Autozone says 02 is bad, consider that the root cause might be something else.

 

New ego sensor on the driver's side installed by the dealer under warranty and I'm on the road again. I'll take a trip tomorrow so I'll get to see if my mileage improves. I've been working had to get it over 15 mpg.

I've heard that the warranty for emissions is 5 year 50k. Is that right?