I have a 1998 Explorer XLT with the 5.0L V8. My check engine light has been on and off sporadically for the past two months. Lately, it has been on more than off. I brought it to a local place to diagnose the problem. Both upper O2 sensors are shot. They want $340 to replace them.

I called a local parts store and can order them for $59 apiece. The local Ford dealer wants $116.95 per unit.

What kind of difficulty level am I looking at if I tackle this myself? Any advice?

Thanks,
Eric

 

It's not likely that both O-2's have gone bad at the same time

Lots of times the O-2's are just messengers for problems elsewhere.
A vacuum leak will cause an O-2 sensor lean code, and replacing the O'2s wont fix a vac leak.

Best bet is to take it to Autozone etc & have them pull the trouble codes which wont cost you anything & then post the codes here.

 

You can probably do this job yourself. The parts are under $50 each at AutoZone and you can borrow their 02 socket for free.

The left side sensor can be replaced in under 15 minutes. It's close to the oil pan and unplugs easily. The right side is a challenge because of its plug location. That plug is basically on top of the tranny. If your arms are the size of Olive Oyl's, you can reach right up there and pull the plug in no time. I had to remove the center console and then the wire was simple to unplug. That console takes a bit of effort to remove. The do-it-yourself price is less than $100.

 

Bring us the code number(s) and we can help if we're around.

Both O2's are likely just fine, as already noted.


We're glad to save you the disappointment of throwing money at parts for no reason.

 

I didn't get the code from the shop. There is no Auto Zone in my area that I know of. Maybe I'll replace the left side first and see if that solves the problem. Thanks for the input everyone. The Pep Boys store has them for $49.99 each.

 

alot of codes tell you that the o2 sensors are bad. i had a check engine come on in my 97 5.0 that said both o2's are bad, and it ended up being the intake manifold gasket needed to be replaced. before you spend the money on new o2 sensors, post the codes here. its most likely another problem. i'm thinking an air leak somewhere......

btw if you do wanna replace them, do it yourself. they are fairly easy to do.

p.s. and on my 92 4.0 a while back, check engine pointed to a o2 sensor passenger side being out, ended up the IAC needed replacing.....

 

Like Alfred & Beast said, why waste your money on parts that you probably dont need.

Do a google search on Actron cp-9125.
With this very handy & very easy to use little gadget you can pull your own trouble codes in a couple of minutes.

 

If the local shop checked the codes and it indicated slow response from both O2 sensors, they may indeed be bad. I would check with the shop to see what codes they came up with, since you already had them check it out and especially if you paid them to diagnose the problem. If your vehicle has over 100,000 miles and they have never been replaced it is not a bad idea to do so as preventative maintenance, and it just might improve gas milage. Make sure when they say "upper" that it is the sensors before the catalytic converter. If you replace them yourself viiidude is right on, you will have to remove the console and go in from the top. Not that big of a deal once you decide to go for it.

 

Well from what I was told, there are 4 Oxygen sensors and I was told the upper two are bad. I assumed he meant the front since the other two are right before and after the catalyst if I am not mistaken.

They did not give me the codes but I was told the heat sensor in each was bad. I don't know what that means. Anyway, the shop has never wronged me but I don't want to spend that kind of money to fix them. The car will run fine except it will burn a little more fuel. My next inspection is not for 10 months anyway.

The vehicle has 83k on it. I bought it at 54k so I'm sure they're originals. I am going to search the Auto Zone site and see if there are any relatively closeby and I'll get the codes and post them here.

Thanks for the help everyone.

Eric

 

If the problem is with the heater circuit, the codes would be P0135 and P0155. It would be very unlikely that the actual problem is the O2 sensors if they both went bad at the same time. It sounds like some wiring circuit problem or a fuse, not the sensors.

 

Yeah, it might be a blown fuse. Take a look at the fuse list in your owners manual & check the "Hego system" fuse.

 

Thanks for the tips. I found an Auto Zone about 20-25 minutes away, not bad. I will check the fuses as well. Thanks again!

Eric

 

1996 ford explorer O2 says bank 2 cant find it only see one.

 

Its going to be on the left side of the engine/truck as your facing the front of it, and its going to be pre-cat. So find your cat and work your way towards the engine. It is sitting on top of the exhaust pipe. I don't have my 5.0L anymore for a reference but if I remember correctly, that's where it is.

 

THANKS LOOKED, STILL DID NOT FIND IT,ONLY ONE THE BOOK SAID SOME CAME WITH JUST ONE ITS AN EARLY MODEL 3/96 V8