Hello all,

I just bought a 2001 qx4 and it did not pass smog.
Codes
P0300 - fsm pg. EC320
P0420 - fsm pg. EC347
P0505 - fsm EC422
P0720 - fsm AT124

I was planning on swapping out the IAC valve so I purchased a OBDII scanner. 20 days later I am still waiting for my OBDII scanner to arrive so I can further troubleshoot myself. In the meantime I took it by a shop had them clear the codes so they could come back and help determine them best order to tackle them. They said when they scanned it it had 17 codes vs the 4 it failed smog for, they replaced the swirl valve and cleared one of the codes but still not complete. Just wanted to jump on here and see if anyone may be able to give me some golden advice on this truck I plan on waiting for my scanner so I can do more repairs myself.

If you are going to do the necessary work yourself, purchase a good repair manual. I have always liked the Haynes Repair Manual more than the Chilton Repair Manual but they are both good. Purchase a reliable multimeter. Spelled out in the repair manuals are simple tests, using the multimeter, to determine faults with various sensors and valves. Be aware that many scan tool fault codes could be symptoms triggered by other components with faults as well. With so many fault codes indicated, it may take quite awhile to track down the real problems but the only way you are going to do it is to study the repair manual and do what you can without guessing. Infinity and Nissan service shops have specialized diagnostic hardware and software so they have an advantage of getting everything done right but it could be costly. It might even be necessary, unfortunately.

Seventeen codes? Sounds like you have more trouble than simply passing emission...

Please if you know of a Haynes/Chilton for this 2001 qx4 please link to it or advise where to find as I have asked and looked. I have a multimeter and knowledge of how to use properly. I still haven't received the scanner I bought. I think I will just get one at AutoZone, any advice on which one to get?

EBiN5446 wrote: ↑

Mon Sep 30, 2019 6:57 am

Please if you know of a Haynes/Chilton for this 2001 qx4 please link to it or advise where to find as I have asked and looked. I have a multimeter and knowledge of how to use properly. I still haven't received the scanner I bought. I think I will just get one at AutoZone, any advice on which one to get?

Uh, have you tried Amazon? They might not list one specifically for a QX4, but look for one for a Pathfinder of the same year. There are a few differences, and I think 01 had a bunch of mid year changes, like the engine for one, but Pathfinder and QX4 are 95%+ the same.

On the smog codes, at least post what they are not just the number, there are a ton of them and I only know a couple off the top of my head.

I have asked at AutoZone each time I went even for a Pathfinder Haynes to no avail. I had looked on Amazon for the Infiniti qx ones had not for the Pathfinder, in the cart now.

As for the smog codes this is all new to me. I have given as much information as I have regarding this thus the reason I quickly jumped on here looking for guidance. Once I get a damn scanner I can post what the actual codes come out as.

The FSM is on this forum. It's in the sticky:

pathfinder-qx4-general-information-and-q-a-t549378.html

No need for a Hanyes manual, which you probably won't find anyway. I don't think it exists to be honest.

Also, you should be able to find and buy a basic code reader at any car parts store for a pretty good price.
Ordering one and then waiting weeks seems kind of silly.

Buzzman wrote: ↑

Mon Sep 30, 2019 7:00 pm

The FSM is on this forum. It's in the sticky:

pathfinder-qx4-general-information-and-q-a-t549378.html

No need for a Hanyes manual, which you probably won't find anyway. I don't think it exists to be honest.

Also, you should be able to find and buy a basic code reader at any car parts store for a pretty good price.
Ordering one and then waiting weeks seems kind of silly.

Others are fond of the factory manual, I'm not, but I can be a contrarian. But the Haynes isn't hard to find. https://www.amazon.com/Nissan-Frontier- ... way&sr=8-2

EBiN5446 wrote: ↑

Mon Sep 30, 2019 5:43 pm

As for the smog codes this is all new to me. I have given as much information as I have regarding this thus the reason I quickly jumped on here looking for guidance. Once I get a damn scanner I can post what the actual codes come out as.

OK, this is probably going to come across as me being a complete a******* when I only mean to be a little harsh. But c'mon, it's 2019, you've got a computer and I assume you know how to Google or else you wouldn't be here. It's OBDII codes, do a simple search, like type in OBDII P0300. Or list of OBDII codes.



There are hundreds of codes, just giving a number isn't very helpful.

My apologies for being harsh, perhaps I've been around forums too long and perhaps I have unrealistic expectations but while trying to help I also try to show how to find answers..

For the record the last vehicle I owned was a 1980. Yes I know how to use Yahoo hence the reason I quoted which pages these codes lead me to in the factory service manual. I'm gonna get a scanner soon.

Side note from the smog.

The shifter button will not engage in the morning I have to push it multiple times before it will engage fully and allow me to shift out of park. I have been successful every morning thus far so haven't had it on priority but it is annoying. Anyone have thoughts on that?

I can't seem to find a hard copy Haynes or Chilton repair manual for the QX4 but there is a Chilton online subscription for the repair manual. The FSM is great but it lacks removal and installation details I find most useful in the Haynes manual I have for my Pathfinder. The link to the online Chilton is http://repair.chiltondiy.com/Pub/DIY/Pr ... air&b=6799
I could not find anything online by Haynes.

Update: I got a scanner the codes that showed today are
P0300
P0720
P1145
P1140
P0160
I erased them to see what shows up first.

still trying to figure out why you purchased this vehicle.....

THere is definitely a haynes manual. I own one. You can get yours here. I highly recommend it.

https://haynes.com/en-us/nissan/pathfinder/1996-2004

P1140 and P1145 could be the sensors or could be dirty oil. I would change oil and filter first. I wrestled with similar codes with VVT issues for a while. I ended up replacing all camshaft and crankshaft sensors and 1 solenoid at Nissans suggestion. I think what it really needed was an OEM bank 2 VVT camshaft sensor and a long drive on the highway as that is what seemed to have fixed it. I got the sensor at a junk yard. Once I fixed that it cleared my other two codes as well.

If the car is running fine it is likely just the sensors. Just my opinion. I am not a mechanic.

If you buy sensors online make sure you get japanese or taiwan manufacture. Or go OEM.

R50JR - was not my best decision...

This thing has many more issues than just these codes showing. I think the 4wd somehow had been always on so someone decided to remove the front driveshaft. It drives decently for My travels. I have the haynes now as well. Now I just need to decide what to replace first and start the process.

Any reason not to use duralast/AutoZone sensors? Any preferred vendor for best/most appropriate sensors?