O2 Sensor questions...

[bluesheep]

I took my 1997 Explorer XLT (4.0L EFI) to the mechanic today to get a valve replaced. When I was there I asked him to check the codes because I have the check engine light on and I have to get emissions testing done in a month. He said it came back with a couple codes, he showed me but I don't remember what they are, then pointed out a couple of things under the engine that needed to be replaced. He was talking about the o2 sensor being the major problem. He pointed to a round, disc shaped part on the drivers-side of the engine. I've attached a diagram, it's within the red-circled area (but not in the diagram).

http://3.bp.blogspot.com/_O7i7aMItbu4/SPTeBXtTIMI/AAAAAAAAAAM/9m2CPTZ9oQ8/s1600-h/sensor.jpg

Can anyone tell me what this part could be and if it is in fact an o2 sensor and if it's something I can replace myself?

Thanks...

also, first time post - long time viewer. Fixed my heater because of this link someone posted here... http://www.blenddoorfix.netfirms.com/

 

[Dan Whitaker]

There are several things with in the red circle which cam cause a CEL (check engine light)

Yes there is such a thing as oxygen sensors. There are four of them. If you have some basic mechanical abilities you can replace them. You will need a special tool which most parts stores loan out or you can buy one for around $10-$15.

 

[bluesheep]

I've heard there are more than one. The one he pointed to doesn't look like any I've seen before. It kinda looks like a flying saucer with a hose or wire hooked to it.

here's a picture I just took of the part in question...

http://1.bp.blogspot.com/_O7i7aMItbu4/SPT3DJ4eqaI/AAAAAAAAAAU/3ke4f2ExNR0/s1600-h/sensor2.jpg

I also have the part number, but nothing comes up in a parts search... Ford F57E-9D460-A2D B86.

 

[Dan Whitaker]

That is your EGR valve.

 

[bluesheep]

okay... I found this diagram, and yes, it is the EGR valve. He may have been pointing to that as another thing that's wrong. He said it had 2 codes triggering my check engine light.

In this diagram...

http://4.bp.blogspot.com/_O7i7aMItbu4/SPT-Rd6EmcI/AAAAAAAAAAc/2MGzjavj2iA/s1600-h/diagram.gif

...which is the oxygen sensor he would have been pointing to? My guess is number 3, but again, that looks nothing like the parts I've seen labeled as oxygen sensors.

 

[Dan Whitaker]

The oxygen sensors are in the exhuast. Two before the cats & two after.

The diagram you linked shows your EGR (#1) valve, DPFE sensor (#3), EGR tube(#5), Vacuum line (#6)I dont remember what #4 is called.

 

[bluesheep]

Thanks Dan...

If I go get the codes again, will they specify which of the four oxygen sensors are bad? Are they all the same part? This is what I've found online...

http://www.autozone.com/R,82333/veh...partType,00117/shopping/partProductDetail.htm

Thanks!

 

[aldive]

okay... I found this diagram, and yes, it is the EGR valve. He may have been pointing to that as another thing that's wrong. He said it had 2 codes triggering my check engine light.

In this diagram...

http://4.bp.blogspot.com/_O7i7aMItbu4/SPT-Rd6EmcI/AAAAAAAAAAc/2MGzjavj2iA/s1600-h/diagram.gif

...which is the oxygen sensor he would have been pointing to? My guess is number 3, but again, that looks nothing like the parts I've seen labeled as oxygen sensors.

No O2 sensor(s) in that diagram.

 

[aldive]

Thanks Dan...

If I go get the codes again, will they specify which of the four oxygen sensors are bad? Are they all the same part? This is what I've found online...

http://www.autozone.com/R,82333/veh...partType,00117/shopping/partProductDetail.htm

Thanks!

Chances are that O2 sensor(s) codes are not indicating a bad O2 sensor(s), but something upstream as the root of the problem.

Good luck ...

 

[bluesheep]

Thanks Al...

Upstream meaning where exactly? The EGR valve or the DPFE sensor?

Thanks.

 

[aldive]

Upstream means anything before the O2 sensor in question.

 

[bluesheep]

haha... pardon my ignorance, I just don't know where they are (not a car guy at all). If I check the EGR and the DPFE am I getting close?

 

[aldive]

haha... pardon my ignorance, I just don't know where they are (not a car guy at all). If I check the EGR and the DPFE am I getting close?

Getting close to what?

 

[bluesheep]

like you said, upstream from the o2 sensors. Dan mentioned where thethe o2 sensors are at, but I'm not familiar enough with the engine to know where that is. I do know where the EGR and DPFE are at, just wondering if that's what your saying is where I should be looking.

 

[Dan Whitaker]

Thanks Dan...

If I go get the codes again, will they specify which of the four oxygen sensors are bad? Are they all the same part? This is what I've found online...

http://www.autozone.com/R,82333/veh...partType,00117/shopping/partProductDetail.htm

Thanks!

Have the codes read again. Have the part's store that reads them write the codes down and post them here.

Then it will be much easier than chaising our tails trying to figure out what is wrong.

 

[sport'96]

if you don't know where the o2 sensors are, then why are you trying to fix the truck yourself???? look at the picture of the o2 sensor on autozone's website, crawl under the truck, look at the exhaust pipes, there will be 1 on each side of the motor, before the pipes come together at the collector tube, there will be one after the catalytic converter also. you can rent a o2 sensor socket from autozone, or just use a 7/8 in wrench, it does the same thing, and on mine, i didn't even have enough room to get the socket on with a ratchet, so i just used a wrench. autozone should also be able to tell you which sensor it is, and which one to get. my local autozone has their own scanner, and will scan your vehical for free. good luck. matt.

 

[bluesheep]

if you don't know where the o2 sensors are, then why are you trying to fix the truck yourself???? look at the picture of the o2 sensor on autozone's website, crawl under the truck, look at the exhaust pipes, there will be 1 on each side of the motor, before the pipes come together at the collector tube, there will be one after the catalytic converter also. you can rent a o2 sensor socket from autozone, or just use a 7/8 in wrench, it does the same thing, and on mine, i didn't even have enough room to get the socket on with a ratchet, so i just used a wrench. autozone should also be able to tell you which sensor it is, and which one to get. my local autozone has their own scanner, and will scan your vehical for free. good luck. matt.

Matt,

I'm trying to fix my car because I don't want to pay the outrageous labor costs mechanics charge to do the work when I'm perfectly capable of doing it myself. I just needed to know what and where I needed to start. I will be taking my truck in tomorrow to get the sensors checked and I'll go from there. My confusion was that the guy looking at my car was pointing at things on my engine, not underneath near the exhaust.

Thanks.

 

[Doubt Incarnate]

that guy must have been pulling your leg then. not saying he isnt right about the codes, but o2 sensors are generally under the car. there may be one or 2 you can get from up top, they will be in the exaust parts. and what effects them is anything from the air that gets sucked in the filter all the way to the spark that ignites the cylinder before its exhausted. we need to actual codes and explinations to help.

 

[Max Sharratt]

check engine light on

I had no porblems with the CEL until a few weeks ago when the fuel pump on my 97XLT died on me - this was fairly catastophic as it happened in a crowded parking lot and as I couldn't start the hydraulic direction wouldn't work which made the vehicle unmanouverable. Finally I got it to fire and headed straight for my local mechanic who tested the pump pressure which showed the pump had failed. In retrospect there were warnings that the pump was about to fail such as a few weeks of requiring 2 or 3 attempts to get the motor to fire and hesitancy in 2nd gear as I pulled away.
Anyway, back to the CEL. I replaced the fuel pump but then the CEL came on and stayed on. My local mechanic did a scan which indicated egr valve problems. I had to get a colleague in Salt Lake to buy a replacement egr valve and courier it to me. Saturday we fitted the new egr valve but after 40km the CEL came back on. Fitting the egr involved disconnecting the battery which explains why the CEL came on only after 40km. I am now wondering whether getting my mechanic to zero the OBDII will be enough or whether I have now to replace the egr solenoid, egr pressure sensor or even the O2 sensors. Anyone out there with any suggestions?