O2 sensor problem after major service

[thunderca]

I bought my 1998 pathfinder to the garage to do the major service at 144000km. The major service include changing all the fluid, timing belt, spark plug... and emissions test. My emission test pass without any problems. 2 weeks after the service I started to get the engine light when I was driving on the highway. I brought my car back to the same garage. After checking the code, he said my O2 sensor might have die. He reset the code and tell me to come back when the light come back on again. 2 week has passed the engine light come on again when I was driving on the highway. I bring it to the shop and he said O2 sensor is dead and I need to replace 2 of the O2 sensor. The problems don’t seem to stop there. After the major service I also recognized that the engine vibrates suddenly when my pathfinder is at 1000 rpm. The vibration would go away when it is higher or lower than 1000rpm (I never had this problem before). After the major service I also noticed that my pathfinder seems to have a harder time starting than before (My garage suggested me to change the battery). Do you think my garaged changed something wrong and caused all these problems? Or is it a coincident that I just need to change O2 sensor and battery too. What should I do? Should I changed the O2 sensor as he said and all the problem will go away? Please help.

 

Does anyone know if there are 4 O2 sensor in 1998 pathfinder? And how can you tell if it is the driver or passenger side sensor that I need to change? I heard changing O2 sensor is very easy, is that true? Thanks for your help.

[94extreme]

no idea how many o2 seonsors there are on your truck but the shudder of the engine maybe related to it/them being bad

[Trainman]

I had an O2 sensor go at 75,000 km so 144,000 km may not be unreasonable. Cost about $220 CDN for the dealer to do it. I ran it for about 5,000 km with the SES light going on/off with out any problems.

 

Try replacing the sensor and see what happens. If you had all this work done at a Nissan dealer, it will be covered by warranty. Regardless, take it back and get the mechanic to get rid of the vibration.

 

Good luck, let us know how you make out.

[thunderca]

I had an O2 sensor go at 75,000 km so 144,000 km may not be unreasonable. Cost about $220 CDN for the dealer to do it. I ran it for about 5,000 km with the SES light going on/off with out any problems.

 

Try replacing the sensor and see what happens. If you had all this work done at a Nissan dealer, it will be covered by warranty. Regardless, take it back and get the mechanic to get rid of the vibration.

 

Good luck, let us know how you make out.

Oh this is the second time having my O2 fail. The first time was at 43093km on aug 2000. It was under warranity, so It was free to get that fix. I had no idear if it was left or right side that was changed though. On the invoice it said

 

DE47A1 Replace Rear O2 Sensor

90 JIM LIC#:S

WPNIS 0.80

1 226A1-0W002 Sensor

 

Does anyone understand what that mean? I guess 226A1-0W002 is the part number but I can't find any information about it on the web.

 

I think there are 4 02 sensor on my truck. I checked all over the web it always pop up with 4 different sensors that I can buy. I justed checked the prices with canadian tire it showed up 4 different sensor too. The price at canadian tire are not much cheaper than dealer though. The left rear side is around 100 but the rear right side is 225. As for the front 02 sensor they are simular prices with the right side being very expensive.

 

I called nissan, the dealer wanted $255can + tax to get one O2 replace. If i just buy the parts alone it is only $132 + tax. So if I do it myself I can changed both at the same price. I have read other thread that changing 02 sensor can help fuel economy. Some people even advice the change left and right together so that the reading will balance. I could use some gas milage improvement when the gas price are rising every week.

[Precise1]

I don't know the O2 sensor set up on the 98s, but if the ECU says its dead, believe it (cant hurt to check the wiring first though).

As for the hard starting, does the motor crank slower ? That would be the battery... It may be the dead O2 sensor is confusing the ECU at start up and it is setting wierd mixtures that may make the motor more difficult to start. That would involve more cranking time. Which is it ?

 

B

[thunderca]

I don't know the O2 sensor set up on the 98s, but if the ECU says its dead, believe it (cant hurt to check the wiring first though).

As for the hard starting, does the motor crank slower ? That would be the battery... It may be the dead O2 sensor is confusing the ECU at start up and it is setting wierd mixtures that may make the motor more difficult to start. That would involve more cranking time. Which is it ?

 

B

Well my gararge guy read the code for me he said for sure that the O2 sensor is dead. I saw the code was something rear. The mechanic said rear for sure.

 

Right now I still have no problem starting. It still start fine. But it just take more turns for the starter to start the engine. Before I had all these things change I turn the keys the truck would start almost instantly. Now I turn the key it takes slightly longer (may be 1.5x longer).

 

So you do u think it is just a coincidence that my O2 sensor die? Or do you think my mechanic made some wrong adjustment to my car on the previous service (could he had adjust the engine timming wrong with he changed the timming belt)? I am a beginner in fixing car, freel free to give me your comment. Thanks in advance.

 

P.S. I just found the store http://oxygesensors.com The price is low there. Does anyone have any experiences with it? Do you know if Denso 02 sensor are the nissan OEM parts? Thanks

[Trainman]

P.S.  I just found the store http://oxygesensors.com  The price is low there.  Does anyone have any experiences with it?  Do you know if Denso 02 sensor are the nissan OEM parts?  Thanks

The one that just came out of my truck was a Bosch, with a Nissan logo stamp on it. It was also one of the rears.

 

As for others, do not forget the dollar difference (you quoted in km so I guess you are not in the US), shipping and duties. Also, the dealer installed item is guaranteed for 20,000 km/12 months (at least in Canada).

 

Edit: Try this web site as well: Bosch4Less (for my truck, thier price was about the same after landing in Canada as the dealers).

Edited August 20, 2005 by Trainman

[thunderca]

P.S.  I just found the store http://oxygesensors.com  The price is low there.  Does anyone have any experiences with it?  Do you know if Denso 02 sensor are the nissan OEM parts?  Thanks

The one that just came out of my truck was a Bosch, with a Nissan logo stamp on it. It was also one of the rears.

 

As for others, do not forget the dollar difference (you quoted in km so I guess you are not in the US), shipping and duties. Also, the dealer installed item is guaranteed for 20,000 km/12 months (at least in Canada).

 

Edit: Try this web site as well: Bosch4Less (for my truck, thier price was about the same after landing in Canada as the dealers).

Thanks for the information. I craw under my truck this afternoon and I saw found all 4 of the O2 sensor in my truck. I took a close look at the two rear sensor and they both said Bosch on it (I didn't see the nissan logo but it might be there). It does look pretty simple to change. i just need to unscrew the o2 sensor rewire the wire and just plugin into the connector. The only problem i might face is I cannot take the O2 sensor out becuase it is rusted on the pipe. Are there any tips on removing rusted nuts other than using WD40 on it?

 

As for warranity Bosch4Less gives out 90 days and no hassle returns. I have no idear what the dealer will give me if i was just to buy the parts. Do they even allow returns? I know canadian tire don't allow return on the O2 sensor.

[94extreme]

PB Blaster work AWESOME on rusted bolts and chit... let it work for as long as you can park your truck.. a couple of days would be ideal.. soak it ever so often.. mine also had a spot weld on it that was a major pain to deal with..

 

search the web hard.. i found sensors for about half price.. if you're near the US border come in find and AutoZone, Napa or whatever and purchase the darn things here..

[thunderca]

PB Blaster work AWESOME on rusted bolts and chit... let it work for as long as you can park your truck.. a couple of days would be ideal.. soak it ever so often.. mine also had a spot weld on it that was a major pain to deal with..

 

search the web hard.. i found sensors for about half price.. if you're near the US border come in find and AutoZone, Napa or whatever and purchase the darn things here..

Oh your O2 was spot welded onto the pipe? How were you about able to take it out and put the new one on? Did you have to weld it back on also?

 

As for sensor I know the exact part that I need. For 98 Pathfinder I need.

Bosch Part # 13257 (Rear Left)

Bosch Part # 13264 (Rear Right)

I will try to call around and see if I can get some prices for it. I call ParSource and canadian tire their price almost identice with the right side over $200. I don't see why the right side being so expensive.

 

PB Blaster I have to see if I can get that product in Canada.

Thanks

[Precise1]

tips on removing rusted nuts other than using WD40 on it?

While WD-40 is better than nothing, it is not really a penetrant per se. Read this for options...

http://www.nissanpathfinders.net/forum/index.php?showtopic=5495

repeated applications and allowing it to soak is highly rcommended. Also, giving it a few sharp whacks with a hammer (without damaging the wrench flats) can break loose rust and corrosion. If it is still stubborn, try heating up the pipe around the sensor with a torch to expand the metal. If you don't have a torch, you can buy one for $20 and they are handy for all sorts of other things. Spot welds usually have to be ground (filed,etc) off. Good luck !

 

B

[94extreme]

if you don't have pb use whatever you have.. liquid wrench, wd40.. they all help.. does too.

 

well, i stripped the old sensor.. then i ended up chipping all the rust off from the area.. i sure didn't see it untill i got all that crud off of there. i remember getting out the sawzall ... i cut the weld best i could with that.. it was kind of towards the top.. a real bitch.. now the new sensor x-threaded big time but it seems to not be leaking. i just put a gasket-in-a-tube around it to help it seal and left it.. seems to work ok.

[94extreme]

yeah, use the torch to start with..

[thunderca]

When they say left and right oxygen sensor. Which side is left? The driver side?

[thunderca]

I finally changed my two rear O2 sensor. It was easer than i though. I wasn't able to buy PB blaster in canada. But I bough liquid rench. I spray on the and the O2 sensor came out pretty easy with a 22mm rench. The hardest part I find in change the O2 sensor is re-wireing. That took me a few hours because it had to go though a few tight places. After the O2 was in stall I notice I am not getting the 1k vibration from the engine anymore. So everything is good. But now I wonder if it was my mechanic that broke my O2 sensor. I had him remove all my heat shields around my exhaust system and he seems to just rip out everything. Some screws weren't even undone. I think he might have koncked on my sensors and damage it. O2 sensor seems to be quite sensitive it is even written that it can't be drop or it will be damaged. Anyway thanks for eveyone who helped me! Thanks

[94extreme]

glad to hear it's good to go!

[Precise1]

Glad it went smoothly Bud ! Most jobs aren't as hard as they appear. Patience and the right tools go a long way !

 

I had him remove all my heat shields around my exhaust system and he seems to just rip out everything. Some screws weren't even undone

 

Um... Excuse me ? If thats how he works, I wouldn't go back to him.

 

B

[thunderca]

Glad it went smoothly Bud ! Most jobs aren't as hard as they appear. Patience and the right tools go a long way !

 

 

 

Um... Excuse me ? If thats how he works, I wouldn't go back to him.

 

B

Yes, I think he literally rip all the heat shields off.

[Clayman]

How's it running now?

 

I have an 87 Pathy w/ a 4 wire pre-heated single O2... and it runs like hell without it. the idle's all messed up and and she chugs like a farm truck.

 

Take Care,

Clay

[FloydMax]

I bought my 1998 pathfinder to the garage to do the major service at 144000km. The major service include changing all the fluid, timing belt, spark plug... and emissions test. My emission test pass without any problems. 2 weeks after the service I started to get the engine light when I was driving on the highway. I brought my car back to the same garage. After checking the code, he said my O2 sensor might have die. He reset the code and tell me to come back when the light come back on again. 2 week has passed the engine light come on again when I was driving on the highway. I bring it to the shop and he said O2 sensor is dead and I need to replace 2 of the O2 sensor. The problems don’t seem to stop there. After the major service I also recognized that the engine vibrates suddenly when my pathfinder is at 1000 rpm. The vibration would go away when it is higher or lower than 1000rpm (I never had this problem before). After the major service I also noticed that my pathfinder seems to have a harder time starting than before (My garage suggested me to change the battery). Do you think my garaged changed something wrong and caused all these problems? Or is it a coincident that I just need to change O2 sensor and battery too. What should I do? Should I changed the O2 sensor as he said and all the problem will go away? Please help.

 

Does anyone know if there are 4 O2 sensor in 1998 pathfinder? And how can you tell if it is the driver or passenger side sensor that I need to change? I heard changing O2 sensor is very easy, is that true? Thanks for your help.

Hate to say this, but my guess is some mechanic didn't put an ignition wire pressed fully into the distributor. Result: an O2 sensor bites the dust (carbon) , eventually the catalytic converter, the Pathy starts hard (one cylinder not firing until the revs are up) etc etc. Ran into it a few years ago with my wife's Honda. Kept giving trouble and that's not like a Honda. So I started checking everything (I'm paranoid that way). Found a wire not "pushed" into the distributor nipple. The boot was on good, but the wire had been backed off from full contact. Said nothing...pushed it in myself and brought the car in to be "checked" again for a "pretend" hesitation. When we picked up the car, one wire to the distributor was not making full contact AGAIN!!!. The boot was fully pushed on but the wire had been backed out of the nipple. Definitely a scam.

 

Concluded it was intentional (blue collar revenge?) and haven't been to that garage since.

 

Consumer Reports found that 50% of all car repairs are either fabrications of breakdown, unnecessary, overcharged or done poorly. Buyer beware!

[FloydMax]

Personally, I'd get my vehicle out of there and when I was free and clear, I would tell them why I won't do business with them anymore. You got the picture... suddenly your car is having all these "problems". Coincidence? Yeah, they coincidentally screwed things up so you would have these problems. Suggest you read about auto mechanics or get a repair manual from Nissan. It isn't that difficult and can be rather relaxing to fix your own car...sense of satisfaction.

 

Sorry you are having these problems, but I am very suspicious of the garage.

[thunderca]

Hate to say this, but my guess is some mechanic didn't put an ignition wire pressed fully into the distributor. Result: an O2 sensor bites the dust (carbon) , eventually the catalytic converter, the Pathy starts hard (one cylinder not firing until the revs are up) etc etc. Ran into it a few years ago with my wife's Honda. Kept giving trouble and that's not like a Honda. So I started checking everything (I'm paranoid that way). Found a wire not "pushed" into the distributor nipple. The boot was on good, but the wire had been backed off from full contact. Said nothing...pushed it in myself and brought the car in to be "checked" again for a "pretend" hesitation. When we picked up the car, one wire to the distributor was not making full contact AGAIN!!!. The boot was fully pushed on but the wire had been backed out of the nipple. Definitely a scam.

 

Concluded it was intentional (blue collar revenge?) and haven't been to that garage since.

 

Consumer Reports found that 50% of all car repairs are either fabrications of breakdown, unnecessary, overcharged or done poorly. Buyer beware!

ignition wire pressed fully into the distributor? Do you just have to look at the distributor and check the cable? Do you have a picture to show.

 

Man next time I think i will bring my car to the nissan dealer for oil change theen they might be able to see little things that I don't see. At least I don't think my dealer would do such a dishonest thing.

[XPLORx4]

FYI, none of the O2 sensors do anything while the truck is being started and when the engine is cold. The readings from the O2 sensors have no effect on fuel management until the engine is warmed up and the system goes into "closed loop" monitoring. When the coolant temperature is low, the ECU uses preprogrammed fuel settings, and ignores the O2 sensors. (This is known as "open loop".)

 

The only purpose of the front O2 sensors is to monitor the air/fuel mixture, which tells the ECM how long to leave the fuel injectors open. The oxygen content in the exhaust varies based on differences from the ideal "stoichiometric" air to fuel ratio of 14.7:1.

 

The rear O2 sensors are only used to determine whether the catalytic converters are functioning properly. If the cats are not operating properly, the rear O2 sensor will set a DTC (diagnostic trouble code). They do not control how well the truck runs.

 

If your truck isn't running as smoothly as it was before (while cold) you may have problems with ignition components or a vacuum leak. If the problem only occurs at a specified RPM, it could be caused by a loose part that vibrates only at a certain resonant frequency.

[thunderca]

FYI, none of the O2 sensors do anything while the truck is being started and when the engine is cold. The readings from the O2 sensors have no effect on fuel management until the engine is warmed up and the system goes into "closed loop" monitoring. When the coolant temperature is low, the ECU uses preprogrammed fuel settings, and ignores the O2 sensors. (This is known as "open loop".)

 

The only purpose of the front O2 sensors is to monitor the air/fuel mixture, which tells the ECM how long to leave the fuel injectors open. The oxygen content in the exhaust varies based on differences from the ideal "stoichiometric" air to fuel ratio of 14.7:1.

 

The rear O2 sensors are only used to determine whether the catalytic converters are functioning properly. If the cats are not operating properly, the rear O2 sensor will set a DTC (diagnostic trouble code). They do not control how well the truck runs.

 

If your truck isn't running as smoothly as it was before (while cold) you may have problems with ignition components or a vacuum leak. If the problem only occurs at a specified RPM, it could be caused by a loose part that vibrates only at a certain resonant frequency.

Thanks the the O2 sensors explaination. I read somewhere before than the O2 at the back does not effect on fuel management. Now that you have explained it, I understand why.

 

After driving for a while getting the o2 sensor changed I still notice that at 1k rpm I still get that vibration. It is pretty anoying when I am driving in the traffic. What should I do? Should I take it back to the same mechanic and have him look at it and make him fix it? I am just worry that he didn't do my timming belt propally. Could someone actually do the timming belt incorrectly and the truck can still run?

 

One time I had a friend over and he looked at my truck. He took the spark plug out and he said from looking at the colour of the spark plug it looks like the fuel is burning ok. If the fuel is burning ok can i still have engine problem?

 

Thanks for your advice.

[thunderca]

I went back to the mechanic and told him that I am getting vibration at 1k rpm. He looked at it, rev the engine a few times. Pop open the hood, rav the engine a few times again. He told me there is a problem with my Fan Clutch. He said it is not serious and it doesn't need to be replace fast. Then he saw my O2 sensor wire, I saw him stares at it for a long time. Then he said he has to go talk to another customer. He ran inside and come back in 2 mins. (He probally ran into his office to find his paper work to see if he actually did the o2 sensors.) He came back out while I was try to feel what he feels on the fan. He asked me if i could feel it loose? I saw not really then he asked me if I got all my O2 done? I said yea I did it myself. He was impreased and said oh this is not too hard you could do this youself too. I think he was pissed. But what the heck, I don't think he has done his job propally (I went home and play did what he did and I think he is right the fan clutch is loose). After my timming belt changed I have 2 problems, 1st the o2 now this fraken fan clutch. This fan clutch will cost me over 100US just for parts. I think he must have messed it up when he took out all the belt in my car. After my timming belt change he told me he had also replaced another belt for me for free. I think that free belt must be the belt that drives this fan. I think he must have a hard time putting it on and he screw up something and thats why he had to replace this belt too. What do u guys things? Am i guessing it correctly? Now I have to spend another 100 dollars. This is rediculous. I had no proved that he actually broke the parts too. May be I will try to fix that next week since I am on holiday.