Dealing with pathfinder running too lean intermittently?

[Quaintbucket]

Hey there guys!

 

So I had quite an adventure the last few weeks with my 1997 Pathfinder! Failed my emission test but got 3 months of insurance to help give me time to get it fixed! It currently has 260,000km and is an automatic with 4x4.

 

My test results was pretty normal. Slightly a little higher than average for HCX and CO but my NOX was double the allowable maximum limit. My initial thought at the time was the EGR so I pulled my EGR valve off (after disconnecting the battery of course...) expecting to see a carbon buildup. very very little.

 

I cleaned it anyway, replaced the gasket, and cleaned the port as well. Still dirty but not that bad. Check the vaccuum on it. It's good. Checked to make sure it's working while running. It's good. Checked to see if the engine stumble if I push up the plunger. It did. The EGR is A-OK. For fun, we decided to do a seafoam with the can I bought a few weeks prior! That was enjoyable

 

Drove it around. It felt a little better. Ran a little better. No problems for two weeks until my CEL came on. Life got busy and caught me up with a whole bunch of stuff.

 

Then...

 

My alternator on my pathfinder decided to kill its bearings and had the chance to replace it (after 2 alternators in one day and one wrong belt, Lordco sold me a dud that wouldn't charge the battery and the wrong belt by accident).

 

It was running weird for a while, huge loss of power going uphill (going up a hill at 80km/hr and dropping to 60km/hr in a matter of a second...). My dad brought home his OBDII reader from work and we were able to pull the codes out of it:

 

P0325 - Knock sensor

P0300 - Misfire on Cylinder #1

 

Pathfinder is due for a timing belt change. That's on my to-do list for July but it still doesn't explain the huge loss of power. I was worried the alternator was not good enough or something? Checked the specs, it's the same as what I used to have so that should not be a problem.

 

So I was kinda confused and decided to take a closer look at the knock sensor, check all the connections... what did you know... a wire running from the distributor cap to the intake manifold was loose. I pulled it and cleaned it, put it back nice and tight. Drove it around, power's back to normal! CEL went away on its own. Great news! I didn't clear the code with the OBDII for some reason.

 

Then it came back on in a week later. Called my dad, got ahold of his OBDII, checked the codes.

 

P0171 - System too lean bank 1

P0325 - Knock Sensor

P0300 - Misfire on Cylinder #1

 

I don't think the P0300 is supposed to be there since I didn't clear it last time. I cleared the code this time around and drove around until the CEL came back on. I haven't had a chance to check it yet since the OBDII is still at my dad's place. I'm a little confused though, I cleared the codes but P0325 stayed. Is that normal??

 

The P0171 was the code I've been waiting for a long time now since I failed my Aircare for BC (Can't believe my luck... they're phasing out aircare by December 31 2014 but I can only insure my pathfinder for 3 months! Not good!)

Anyway, so I drove for 3-4 days and the CEL came back on with no weird things happening. It has been doing that for a long time.

I'm taking my pathfinder to my brother in law since he has a can of MAF cleaner since I have a feeling that's the culprit. If that's not the case, then I'm changing the oxygen sensor but I'm not sure which one on Bank 1 (I know that's the passenger side?? but which one? post cat or pre cat?)

I got till August 2nd 2014 to get it fixed. I'm leaving for Hawaii next week and will be back before the end of June. When I come back, I'm working on this and getting it fixed up because I want to ensure it for the full year. Hunting season is coming and I got a major camping trip coming up.

TL;DR: CEL comes on and off on its own during multiple drive cycles. Failed Aircare due to HIGH NOX (everything else is normal). Cleaned EGR, Seafoamed. Will be cleaning MAF. If code comes back, then I'm replacing O2 Sensor.... if that doesn't work... then I'm replacing the cat...

Having said that, I do plan on going for another inspection anyway once I clean the MAF to see how the numbers changed even if I fail ($25/reinspection). Also, I have noticed my fuel economy has been getting worse. I used to get 450km on a full tank and now I'm looking at 400km on a full tank.... this trip around, I think I'm getting 350-375km... that's pretty bad and can't afford to feed it like that.

I got a lot of things I need to do for the Pathfinder pretty soon but refuse to do it until I can get this to pass emission otherwise no point in doing it if I can't drive it! I'm planning on:

• Replacing Timing Belt, Tensioner, Water pump, Camshaft seal
• Replacing bushings on Control arm (saw it's in a rough shape) and trailing arm and anything I'm missing??? I'm just learning to do mechanic stuff under proper supervision
• Replacing valve cover gasket and grommets unless there's a reason not to do it??
• Replacing spark plugs (I think they're original...)
• Replacing rear oil seal (I saw where the oil leak is coming from...
• Replacing tires with BFG AT KO or General Grabber AT2 (depending on my budget) or look for 16" rims so I can get free ZAMBONI TIRES at work (they're 215/85/16 A/T with snowflakes)

Part of me wish I had bought the Isuzu Rodeo or the Trooper but I'm pretty happy with what my pathfinder got me to do and has been a true fellow. It's my hunting rig and daily driver. If it ever ended up dying, I will most likely go and buy a Ford F150/250, Nissan Frontier (can't wait for that update release today!), xterra, or FJ cruiser.

Edited June 11, 2014 by Quaintbucket

[adamzan]

Well p0300 is not cylinder 1 misfire, its random/multiple cylinder misfire. If you have the original spark plugs at 260k, I would seriously start there. The knock sensor code is probably coming up because it is running poorly. I would start with some basic maintenance like the plugs, wires, cap and rotor.

 

Also do not wait too long for the timing bet because if it breaks or slips you're looking at bent valves.

[Quaintbucket]

My bad about the P0300. Yes, it is random/multiple cylinder misfire.

 

I do not know if the spark plugs have been changed before I got this pathfinder and am working under the assumption as if it has not been changed. It is on my list of things to do.

 

I do know that the timing belt was changed approximately 120,000km ago (recommended to change every 109,000 miles = 170000km) according to the service history so I am not terribly worried but doing it anyway.

 

The cylinder misfiring is not a concern for me, but the emission problems as if I don't pass aircare. P0171 was accompanied by no other codes. Am I on the right track cleaning the MAF, checking O2 sensor, and checking for an intake leak (I'm assuming the best way to do it is to spray carb cleaner around the intake seal and watch for a stumble/stall or change in RPM at idle?) before replacing the cat? and which oxygen sensor is more likely to be the problem? The pre cat or post cat on the passenger side?

[adamzan]

Bad spark plugs and a misfire will cause it to not burn properly, and you'll fail the emissions test. Cleaning the MAF never hurts, but I doubt it is your problem. I think you are getting ahead of yourself, and should just start with the tune up items first. Or at least take a plug out and have a look at it. The colour of the plugs will tell you what is going as well.

 

The post cat o2 sensors are there purely to tell the computer if the cats are working properly.

[Slartibartfast]

+1 on the tuneup, but it seems like a misfiring ignition would lead to high CO/unburned fuel, not the lean condition you're fighting with. Cleaning the MAF (and its electrical plug!) and checking the primary O2 sensors sounds like a good start.

 

Also, Zamboni tires?

[Quaintbucket]

I will look at the spark plugs after I clean the MAF and the connecting plug. I'm not sure if I necessarily agree because the failure to ignite would make the vehicle run rich, wouldn't it?

 

I will most likely replace the spark plugs, unless they look relatively new, what type do you guys recommend? I looked at rockauto and I'm taking into consideration that iridium would be best for my purposes since i'm taking my pathfinder into pretty rough elements (extreme temps).

Also, Zamboni tires?

 

I work in an ice rink and we replace them when the studs wear out even though the tires are still 90% treads on them.

 

We're currently rocking Goodyear Duratracs on most of them... and we have extras stored at other facilities. A pick of Firestone Destination, Cooper Discoverer, etc. Most of them are A/T, few are M+S, all with snowflakes (very important!). I got the OK to have them for free since they're not using them anymore. I like free better than $600 minimum.

 

They're 215/85/16. Skinny and tall. I'm currently driving 235/75/15.

Edited June 12, 2014 by Quaintbucket

[Precise1]

I would start with a proper tune up first, clean the MAF and check the resistance for the coolant temp sensor against the FSM listed values, check for any vacuum leaks and exhaust leaks.

 

Yes, failure to ignite would mean rich, except that the o2 sensor would tell the ECU which would lean that side out. Closed loop system means you need to make sure the systems are all working properly, and that includes dizzy cap/rotor, wires and plugs. It only takes a few minutes to pull the #1 plug to get an idea. I have seen this...

 

Assumed original at over 400k kms. Yeah, it ran, but it ran much better with new plugs...

 

B

[Slartibartfast]

Is the OBD1 ECU smart enough to lean out just one bank? It's only got the one O2 sensor.

 

But it does sound reasonable that the computer would read a rich condition and try to lean out.

Edited June 12, 2014 by Slartibartfast

[Precise1]

The R50 (1996 on up) is OBD2 with 4 O2 sensors. You are right though, the WD21 system with the single O2 sensor wouldn't have a clue...

 

B

[Slartibartfast]

Right! Forgot I was in the R50 section. Explains a lot actually.

[Quaintbucket]

Well, I finally got myself to get the time to look at the pathfinder to solve the problem after my vacation.

 

The duct boot pipe to the intake manifold from the air filter cabin was cracked pretty badly underneath (hidden from view). 2 large cracks.

 

It's temporarily fixed with duct tape and I'm ordering one from Amazon since nobody is carrying one. I thought about going to the wrecker but figured I don't want to waste too much time.

 

Ordering a new OBDII scanner as well.

[Quaintbucket]

Well, I got a few new problems popping up now. Flashing check engine light, hesitation in accelerating (RPM), and having a tough time going up the hills. Might be my spark plugs, distr. rotor and cap (they didn't look so hot), and spark wires. I'm ordering those on rockauto soon since locals here are asking for $$$$ instead of $$¢¢.

 

Feels like a misfire. Still waiting for a OBDII Scanner + new duct boot to come in the mail this friday and will work on it this weekend to see what the heck is going on.

 

Weird enough, I put a full tank of gas in my pathfinder and the check engine light went away and it ran slightly better but not that much more. SIGH.

[Quaintbucket]

The check engine light going away did not last. Shortly after that post, the check engine came on during my drive and drove just as rough (felt some misfiring) and lots of hesitation under load.

 

Yesterday, I got so fed up with waiting for my part so I grabbed the split duct boot, wrapped it with silicone tape (very handy to have...) then wrapped it with duct tape. Was a little hard to get back on the intake manifold because I wrapped a little too tight. Hooked everything back up and fired it up.

 

Check engine light was on still (I disconnected the battery as I had to remove some electrical wiring) thought that was weird. Ignored it and drove around. Rode a little rough but not as bad. This morning, drove it to my parents to drop off my kid. Ride was a lot better. Hesitation was still there but it wasn't as severe. I might have a vacuum leak elsewhere on the vehicle that I need to find. Any ideas? I'm thinking of spraying carb cleaner around to see if the engine chokes in places I sprayed in. My hearing isn't so hot so I can't really listen for sounds.

 

Aaaah. Can't wait to get this fixed once and for all so I can smog it and get back to my regular repairs and driving.

[Quaintbucket]

So I finally got the part and OBD2 scanner, Actel MS300.

 

Plugged in the OBD2 to see how my repair did. No more P0171 for the last 3-4 days! Good news to hear

 

My code pulled up P0300 and P0325 (random misfire and knock sensor respectively) which explains 2-3 days ago... I believe. Cold start is noticeably better. I am going to order the parts for tune up. Distributor cap, rotor, spark plugs, wires, pcv, fuel filter, and air filter. I cleaned the air filter w compressed air but that's a temporary fix on a $5 part.

 

Will take it to aircare tomorrow and hope the numbers are significantly better. Was going to do it today but my daughter is not cooperating with her nap... Oh well. Just happy that this might be fixed once and for all.

 

Edit: I also did a 50km drive to go pick up my part. It did have a slight loss of power but no check engine light. I would have thought it was a misfire but didn't feel like it. Might be the TPS but not sure because no code came up...

 

Edit: this is the picture of the broken duct boot before temp repair. If you look, you can see a large crack on the side. There's another one the same size and another one about half the size. I would not be surprised if this caused a huge jump in my nox.

 

Edited July 18, 2014 by Quaintbucket

[OutdoorJack]

STOP. I mean it. I want you to listen very carefully.

 

Don't do anything else—don't buy ANYTHING ELSE—until you complete your tune up!

 

You are wasting precious time doing detective work with data that can't possibly be considered until you complete a basic tune up.

 

Plugs and wires alone may solve EVERYTHING you have mentioned.

 

Besides, you have a sweet child and she deserves every spare moment her papa can find! Don't waste precious moments theorizing about "problems" that are unlikely to exist. (Or at least you can't know if they exist yet.)

 

You're CATs are probably fine, but if you keep dumping unburned fuel from misfires in them, they WILL burn up. (Melt together) Also the case for the O2 sensors which are sensitive to excessive heat and carbon buildup. Guess what happens with each misfire you drive on... Yep, unburned fuel travels into your exhaust pipe sticks to the HOT O2 sensor and burns, making everything hotter and leaving behind carbon buildup—caking occurs and the sensors no longer function. This can also cause your exhaust manifold to crack. These things might be bad already, yes, but none of them are likely to cause a misfire... They are cause BY misfires. Lean mixture included... Computer leans out the mixture when too much unburned gas flows into the exhaust... Maybe. If these things aren't bad yet, they soon will be if you keep driving!! For heavens sake, fix the misfires. Plugs and wires!!! (If injected, misfires can be injectors too. But typically they aren't intermittent or random where a faulty injector is involved.)

 

Mechanically speaking you're acting a little out of order. And I say this with the love of a brother who would help you do the tune-up if I were there, I hope you know this.

 

I remember getting into mechanics and being excited and confused by everything that could potentially be wrong. And intoxicated by the $$$$ I can save!! That was 16 years ago. Done properly, it can save you better than 50%, even with buying tools... Done poorly and it can, and WILL cost you dearly. Follow the advice of fellow mechanics on here and TUNE UP YOUR TRUCK TODAY.

 

Shop classes begin with shop safety, then move on to the first lesson. The Basic Tune-up. It's first because it's the foremost important task to do on any car when you begin trouble-shooting. You have to eliminate the variables one at a time to isolate the problem and this is the easiest way to eliminate the most likely culprits for everything you are describing.

 

Parts should cost no more than $60-$100 in total.

 

This includes:

 

1. Spark plugs—get the basic ones, Nobody needs iridium...PERIOD. There's an extra $15 for a sneak out daddy daughter date.

 

2. Ignition wires (The kit includes coil to distributor wire, and distributor to spark plug wires.) Only buy the basic ones. Two more outings with the little one paid for... Dinner and a movie?

 

3. Distributor Cap & rotor

 

4. Air filter—again get the basic one. Save if $7 or $8. Enough for a back to school gift perhaps? Maybe a small bouquet flowers on the first day of school...oh, she'd MELT.

 

5. Fuel Filter

 

Note: Verify timing—if things are still screwy after a tune up.

 

Your engine needs fuel, air and reliable spark. You've done a lot of great detective work, and it's fun to see your excitement. Now eliminate the most probable cause before moving to the next one.

 

I'll be VERY surprised if ALL of your codes don't disappear and gas mileage return to normal with a basic tune up. Though you might have wrecked an O2 sensor by now, and hopefully not a CAT... If not the codes will automatically clear with 3-5 drive cycles. No OBD-II scanner needed.

 

If you haven't done so already, buy the parts TODAY, before you close this browser window, or app.

 

IMPORTANT!! I believe your engine is an interference engine, which means the valves are synchronized perfectly to open only when the pistons are out of the way. If the timing belt brakes, all of your pistons smash into your valves—wrecking pretty much everything important in the center of your engine.

 

Simply put, your engine self destructs in less time than it takes a human to blink.

 

It's not pretty:

These are from a PT Cruizer, posted to a Dodge Dart forum by a friend.

 

Unless you have $1600-$3800 laying around for an engine swap. Inspect/Change that timing belt immediately!! If you don't know how... Pay someone to do it. Like, tomorrow, before you drive it again. Haha.

 

Please let us know how the tune-up goes! And don't bother posting another update until you do it.

 

Feel free to ask any questions about a tune-up if it's your first time. E.g. Where to put the dielectric grease. How to start a spark plugs in straight so you don't wreck threads in your engine. Etc.

 

There is wealth of knowledge in this forum!

 

Best of luck.

Edited July 19, 2014 by OutdoorJack

[Quaintbucket]

Hey man, I appreciate your kind words and encouragement to spend time with my daughter. I think I need to be clear about what I was talking about before.

 

I do spend a lot of time with my daughter, no worries. She's only 1 year and 4 month old, so we do a lot of walking in the park, going swimming, taking the stroller through the trails, take naps together, etc. on my Fridays and Saturday/Sundays (depending on what day I decide to go to work).

 

I don't think she will care too much for movies and dinner haha. The only time I work on my vehicle is when my wife is home from work and at my parent's with my dad who got 20 years of experience under his belt.

 

We have checked the resistance of the knock sensor harness and it is dead. I already put all the necessary orders in and will be working on it this weekend. My vehicle has NOT done any misfires for a week now. I am positive it has to do with the severe vacuum leak from the cracked duct boot.

 

I did this before I saw your post and I am not terribly concerned with money. I just don't think I need to pay a mechanic for a job that I can do just fine with the help of an experienced mechanic. I have ordered the following parts:

 

Knock Sensor (for relocation)

Knock Sensor Harness (for relocation)

Spark plugs

Spark plug wires

Distributor Cap

Distributor Rotor

Fuel Filter

Air Filter

PCV valve

 

I am also ordering an O2 sensor just in case but will buy it locally so I can return it if it turns out I do not need it. The cats are absolutely fine as far as my father and I can tell.

 

When I said the timing belt is due for a change... I meant to say for another 20k km and it will be done this August. I will also be replacing the water pump, belt tensioner, and any necessary gasket. I realize that I need to get it done sooner than later, but my first and foremost priority is to get this to pass emission.

 

This is what I am doing first in order of importance to me:

 

1. Get this to pass AirCare with tune up and new knock sensor. Taking it to the following day after to test it. If anybody got any other recommendations, now is the time to let me know.

 

2. Replace/Repair suspension components. Vehicle got a slight death rattle going on now and I looked at my bushings and they looked like they've seen better days. This is important for my peace of mind.

• Control arms - Deciding between a full control arm or just bushings
• ALL OTHER BUSHINGS
• Check struts, coils, and cv boots

3. Replace Tires. These tires are old and running low on treads. Sidewalls are showing signs of fatigue. Winter will come soon and I need good tires with healthy treads to get up those hills. I am looking at 30/9.5/r15 on my stock rims otherwise will stick with 235/75/15...

 

4. Timing belt, water pump, etc. change.

 

5. Valve Cover gasket + Intake Manifold Gasket + fuel injectors + whatever other parts are in there. I will pull the old knock sensor out and take a look at it... maybe replace it, who knows.

 

6. Warn locking hubs to extend the life of my new CV joints. Helps that I got a smoking deal at cost for $110 CDN instead of $300 everywhere else.

 

7. fix my rear bumper.

 

8. take it to Nissan dealership for the seatbelts lifetime warranty .

 

9. Any goodies that I feel like getting.

 

My budget is a bit tight but it's there and will pay for all of the stuff I've listed. If I were to get a mechanic to do it for me, it will just be too much and will eliminate everything. Besides, working on my vehicle with my dad gives me a chance to spend more time with him and get to know my pathfinder a lot better. Plus, the experience I will get will also enable me to know my vehicles better and how to do the necessary jobs. I am also taking full advantage of the Nissan FSM at nicoclub to go through the step by step process.

 

I am posting this at work so no valuable daughter/father time was lost.

[Leo98]

When you get the intake manifold off flip it over and i would replace the small coolant hose and clean the IACV.

 

If you get to your timing belt before I get to mine, any helpful tips and information would be appreciated.

Edited July 22, 2014 by Leo98

[Quaintbucket]

This weekend was productive. I spent a good amount of time working on the pathfinder and giving it a tune-up + knock sensor relocation.

 

What I did:

 

1 - Replaced distributor rotor (needed to be replaced. the bit was frayed...)

• Beck/Arnley - Very easy. I had to crank the car a couple of times to rotate the rotor so I can get the nut off and replace it. Do not turn this by hand or else you'll break soemthing/throw off your timing.

 

2 - Replaced distributor cap (it was in fairly ok condition but worn down... replaced it!)

• Beck/Arnley - Very easy. Straight up swapping it. Just remember, the #1 port is facing towards the radiator.

3 - Replaced all spark plugs (NGK 5464)

• This was fairly easy except for #6 which was not visible nor easy to find. I spent a good 10 minutes searching for it by hand so I can throw the spark plug socket on it to take it off and clean it properly. Make sure you find out EXACTLY where it is by hand before you take off the spark plug wire. It will make life a lot easier. Once I found it, it was easy to find it over and over...
• I did this by loosening the spark plugs (do not remove) a little bit and taking the air compressor and blowing out all the dirts around the spark plugs and the surrounding area. Got it nice and clean. You want to do it to avoid getting dirt in the holes... that's a bad day for anyone.
• I did not have to put anti-seize grease on the spark plugs. You can use them I used NGK 5464 (Iridium) with a gap of .044. I checked each one of them beforehand to make sure they were exactly that. I removed one spark plug, replaced that one, and put the spark wire plug on them. Make it easier to track. Odd number on the passenger side, Even number on the driver side. Number going up from front of engine block (closest to rad) to back (closest to windshield wipers). I put them in by putting the spark plug in the spark plug socket (very helpful) with an extension and put them in by hand and turning slowly to make sure it's in properly. You do not want to mess up those threads... you will cry. After you can't turn it anymore, you can use the ratchet. I used 1 or 2 fingers to tighten it. You can use a torque wrench and I would probably recommend it.

4 - Replaced spark plug wires (NGK)

• This is pretty easy. Just remember, odd number on the passenger side, even number on the driver side. Number going up towards the windshield. Make use of harness. I reused the heat shield tape from the old spark plug wire #6 to the new #6 spark plug wire. I was worried because it was so close to the intake manifold. It should be fine without it but why not...?

5 - Replaced fuel filter (Mann MF1005)

 

• Biggest. Pain. In. The. Ass. It was the original fuel filter at 260,000km. Definitely in a big need for a change. Located above the rear axle of the pathfinder. covered in mud. I strongly recommend jacking it up and put two jack stands under the axles. It will make it easier
• The FSM Stated that you must do this:
  1. Remove the fuse for fuel pump. It is located in the change box near the driver side door. The fuse is #15. It will be the second column from the left. 4th from the top. Pull that fuse out and put it in a safe place.
  2. Start the engine and let it stall.
  3. Crank it a couple of times. Once or twice should be fine
  4. Get a bucket ready because once you remove one of the fuel line, there will still be a little bit of fuel....
  5. Remove clamp around filter and hose clamps
  6. Remove filter and replace filter
  7. Plug fuse back in.
  8. Start car. It will stumble a little bit but will start. Just don't force your engine to crank hard. A couple turn over will do the trick.
• #6 is easier said than done. (See a trend happening so far???!!!). It's a tight spot and the fuel line is really tight on the fuel filter. It took a fair bit of struggle to remove the line but I got fed up with the second line that I just cut it and put it on the new one. There was enough of a line for me to get away with that but I recommend having an extra fuel line hose on hand just in case if you end up cutting too much or destroying the hose.
• Dump the fuel out of the filter and watch all the sediments come out of it. Gross.... it was definitely clogging up. I might have to replace the fuel pump but not necessary right now.
• If you cannot reuse the fuel, you can let it sit in a bucket outside. The fuel will evaporate so no big deal. Do not dump it, obviously.

6 - Replaced knock sensor via relocation. I bought the sensor and the harness from ebay. Worked like a charm. The relocation video is awful because the guy was just not showing the wires properly. I used the following parts instead of what he was using.. so dumb.

• Heat shrink tubing (to use in place of the connector plastic)
• Connectors (I cut the outside plastic and pop the inner parts out for connecting the wires)
• Electrical tape that motha fudge bar up.

No more P0325! So cash, brah.

 

I noticed that I had some vibration in my steering wheel at high speed (100km/hr) so I jacked up my front and checked for any play in the wheel. I shooked the wheel back and forth to see if the wheel bearings are ok. They are good. I spun the wheel to listen for any sound, nothing unusual. Checked the wheel to make sure they're not bent... they're ok.

 

It might be my tire sidewalls, alignment (doubt it), balancing, struts, or shocks. The tires will be replaced and balanced and the struts is due for a replacement I believe but I will bring it to NISSAN for the TSB on the driver wheel well to check for rust... I checked it myself and it seems fine but will double check.

 

TODAY IS AIRCARE DAY. I am going right after work and will find out if I pass. If I don't pass... well, damn, I don't know what the hell is up.

 

Hope this post was helpful for you guys.

 

E: Replaced air filter. Forgot that one! Very easy.

Edited July 28, 2014 by Quaintbucket

[Quaintbucket]

Well, moment of truth.

 

 

FAILED.

 

My nox went down very very slightly so intKe air leak was not the problem.

 

Off to the garage I go. I'm taking this into Nissan dealership to run tests or an independent mechanic.

 

No codes in the system. I found out they have previous test results online so I looked at that. It was slowly increasing in NOX so I'm thinking the cat has gone bad but taking this to get tested.

 

I have 2 cats and they run at $340 each at my cost..