[Cryogenix1]

From experience, getting the whole float/pump assembly back thru the top opening can be challenging to say the least. I would be worried that something was forced and maybe slightly bent, causing a float issue.

You should not be smelling any gas when the car is parked. Reading that it took two men to remove the retaining ring gives me concern about the reinstall. A square O-ring is usually between the tank and assembly, prone to partially rolling while fiddling with getting the lock ring into proper position. The float/pump assembly needs to be firmly pressed down on the gasket to prevent any movement.

If the gasket is not an issue, you should check the entire fuel recovery system for loose, broken or missing parts and hoses. Charcoal fuel recovery canister may be at the end of it's life, one of the main reasons there's usually a gas odor from older cars.

I'm not at all confident that they did an acceptable job. Makes me wonder if they were trying to spin the ring the wrong way. Not a speck or smell of fuel around the pump. I never smelled fuel while MO was parked in the garage, only smelled it faintly when driving sometimes.. I think bank 1 running rich is the issue. Could be something new, though. I forgot to mention that the owner/mechanic refunded the labor involved with installing the fuel pump.

EDIT: I had a hard time visualizing two grown men trying to spin off a retaining ring while holding onto the same tool. Since there's no rust on anything, it's likely they were either pushing down too hard and preventing the ring from turning, or they had the tool positioned on the wrong thing.

 

[I need coffee]

Something is now off with this new fuel pump. The gauge read 1/3 of a tank of fuel, and I topped it off. On the last $.30 worth of fuel, gurgling air sounds started happening within the fill tube, and after I removed the gas nozzle, that gurgling air sound continued for a good five seconds. Never had that happen in the 17 years I've owned MO. Then, once starting the car, the fuel gauge only read 3/4 full. I drove around trying to move the fuel around and possibly unstick something, but it did no good. Also tried shutting down and restarting MO several times to see if the needle would bounce up. No good. After about 30 minutes of driving, the needle finally went to F. I've noticed that from time to time my fuel level seems to change quickly from when I last saw it, and I thought maybe I was just remembering it wrong. I'm sure I'm not.

I know there's an electrical connector inside the fuel thank that goes from the new pump to a sensor on the other side of the tank (accessible under the other rear seat) and I don't know if that wiring is getting caught on the float, or if the float wire/arm is bent, or if the arm (or whatever it is) that the float fastens to/into on the fuel pump is getting stuck and then while driving frees itself and provides a reliable reading. It makes me wonder if there's something wrong with the pump, or something wrong with the gasket/O-ring that the puimp seats onto against the top of the gas tank. I haven't looked at the top of the fuel pump since installing that missing green clip, but I have noticed from time to time that I'm smelling a little gas when standing outside, but there's nothing leaking beneath the car. Possible it's just s trickle on the top of the tank that isn't showing a problem with that gasket/O-ring or whatever. Guess I'll check it out. The gurgling air sound that happened this morning has me concerned that something isn't quite right.

UPDATE: No visible or smellable signs of fuel on or around the top of the gas tank, fuel pump or lines. That's a relief. The other day I threw P0172 which relates to bank 1 running too rich, which might be why it smelled of fuel from time to time. Since I have no desire to remove that new fuel pump to see what's up, I guess I'll just live with another quirk. I also noticed a few days ago that I can't get I/M readiness, so I wouldn't be able to pass the State's annual inspection if I had to. Last year, replacing a heated O2 sensor provided a cure for the non-I/M readiness. Yesterday, I was able to get O2 and EVAP to clear, but not CAT. Today, I can't get any of those to clear. I know I've developed an oil leak around bank 1, and I'm guessing one of the plugs might be full of oil and causing some issues. I have been getting a few acceleration hiccups from time... Looks like I'll be tearing into MO over the next few days to replace some things. Instead of installing a new valve cover gasket on bank 1, I might just get a new valve cover that I believe comes with O-rings for the sparkplug well openings. From what I've seen online, you have to bore out the old rings in order to install new ones. Not worth the hassle.

Post the freeze frame data for the P0172. What are long-term fuel trim values for both banks at idle when the engine is at operating temperature?

Your scan tool should have the OBDII diagnostic monitor tests (Mode $06). Check all those and see which ones are failing.

 

[Cryogenix1]

I don't have any freeze frame data for the code. I just erase the codes while driving so I don't have to look a the SES light. I know this car well enough not to be concerned about any thrown codes unless I feel the car is doing something truly strange. That MO threw a "critical CVT failure" error code years ago while on a ten-hour drive, and nothing bad happened, tells me cars today have too much finicky technology that can indicate errors left and right, despite a car running fine. I think I've thrown code P0128 more than a dozen times starting in September, and I just decided to ignore it since I had good heat and no leaks and the engine temp was fine. A few weeks ago I started feeling a few acceleration hiccups going up a hill from a slower speed, and the SES light came on at the top of the hill, so I read it and it was P0172, which I've gotten maybe two more times since, along with a P1778. I know what I need to do...I've just been putting it off because the hiccups are few and far between and controllable by not allowing the RPMs to slack or drop going up a hill. However, MPGs have dropped over the past four weeks, which might be a problem with the plug on bank 1 (or maybe with the vapor canister), probably cylinder #1 if history remains the same. That plug always fouls worse than 3 and 5. And, to try something different this time, in Sept I gapped new bank 2 plugs at .020, and did bank 1 plugs at .040. I was just curious to see how the igntion system would compensate for varied plug gappings. I don't think it really made a difference. MO has driven fine and has had its usual acceleration. In fact, a few days ago, I got the RPMs up to 4500 and MO took off, and didn't throw the P0420 code, which surprised me, However, the cruise control's "set" light started blinking... I really do have fun with this car.

 

[PaulDay]

Unfortunately, what you're calling fun, sound like a long time running nightmare.

Feather the pedal, keep the rpm under so so conditions and all the other hoops is no way to drive a car.

Either you have to much time on your hands, really desperate to keep this car, or just love wondering if you're going to make it home every time you go out, lol.

The saga has gone on way too long. Get rid of it and get anything that you can just get in and drive. I promise you, you'll never look back, except in wonderment that you went that long driving that hunk of junk (Murano or no Murano!).

Good luck and hope you have much better luck with your next car.

Have a good day.

 

[I need coffee]

Yeah, your Murano has given you way too much drama. BTW, you said earier that you know what your next (new?) car is going to be...so what is it?

 

[Cryogenix1]

Unfortunately, what you're calling fun, sound like a long time running nightmare.

Feather the pedal, keep the rpm under so so conditions and all the other hoops is no way to drive a car.

Either you have to much time on your hands, really desperate to keep this car, or just love wondering if you're going to make it home every time you go out, lol.

The saga has gone on way too long. Get rid of it and get anything that you can just get in and drive. I promise you, you'll never look back, except in wonderment that you went that long driving that hunk of junk (Murano or no Murano!).

I don't know anybody throughout my life that's been the sole owner of a car and has put on this much mileage. Most people tend to get rid of their vehicles around the 100K mark. There's a certain degree of something in me that just wants to keep driving MO and doing as little as possible to it to see how much further she can go. I love experimenting with this vehicle because I know I never will again with another vehicle. Once this car's gone, a lot of my mechanical fun will also vanish. And this car's hardly a hunk of junk. She drives smoothly, quietly and is comfortable cruising around in for hours without my hands ever becoming achy or having to shift around in my seat because my ass starts to hurt. While certainly not a dream car, I wouldn't classify MO as a nightmare. And the day I have to wonder if I can make it to point A and back again is the day I finally get rid of MO...or when I hit 300,000 miles. This car has given me no significant reason to think it will break down at any time. I will have a certain amount of regret when I finally donate her. I think what's wrong with most people is, no patience or tolerance/understanding or ability to deal with problems. I don't fall into that group.

This car appears to drive normally for those who have driven it once it's warmed up. Most people don't floor the gas pedal in daily driving or use cruise control all the time, so they'd never know of the high-RPM glitch that sometimes causes the engine to choke. However, I think the new fuel pump took care of some of that, as I said I got the RPMs up to 4500 and MO took off, but I didn't want to risk blowing a head gasket so I backed off. Even doing semi-aggressive driving or cruising up hills, I rarely ever need to get the RPMs over 2800. The acceleration hiccup is something probably 99% of people wouldn't even feel. I feel/hear it because I've owned this car so long and know what it does and when things change. That hiccup only happens under cruise control at the start of one specific hill. Right when the more level road meets the start of that particular curved hill and cruise has to do something different, there's a micro-second of a delay/hesitation and then cruise sends MO up the hill, and three times it's produced P0172. To counter that small delay, I simply apply a bit of pedal just as MO's about to hit that transition (effectively overriding cruise) and she goes smoothly up the hill without throwing that code. I find this kind of stuff fun... Even when the fuel pump crapped out, it was fun trying to go as far as I could, then trying to find a good spot to stop, then trying to see if there was anything I could do to get MO running, etc, etc. Having everything in life perfect or problem-free is really boring. Like I've expressed before, if MO became expensive/cost-prohibitive to own, I would have no problem getting rid of her. At the moment, I'm well ahead of the game and have gotten good bang for my buck in buying her. Some of the stuff I do (such as annual ignition parts and over-the-top oil changes every 2500 miles) I don't really need to do. I do it because it's not that expensive and I enjoy working on cars.

 

[Cryogenix1]

Post the freeze frame data for the P0172. What are long-term fuel trim values for both banks at idle when the engine is at operating temperature?

Shortly after this post, I added a pint of Marvel Mystery Oil to my fuel, and since then I have not been able to produce the P0172 code when trying to. The only code I threw was yesterday when I tried something that PaulDay suggested in a different thread, about flooring the gas pedal and keeping it pinned to test the CVT. I did that for about seven seconds before I chickened out, and the CVT did fine and transitioned fine and the engine didn't choke or sputter or hesitate. About 20 minutes later, as usual, I threw P0420. It usually happens if the RPMs exceed 3000 for more than five seconds. However, in most cases the engine sputtered and the cruise control's set light would start to blink. During yesterday's "pedal to the metal" test, everything was very smooth and normal. Definitely feel the old fuel pump was making the engine choke by not supplying adequate fuel upon higher demand. The fuel trims look fine to me, especially given the age and mileage of the engine and most of its support components.

 

[Cryogenix1]

Some very strange things happening lately. For the second straight morning, MO has not over-tached at all after driving from a cold start. She went from 0-20, 30, 40 without the slightest indication of anything being wrong. And I didn't have to do anything gentle/odd with the gas pedal... I just pressed it normally and away she went. I haven't changed the CVT fluid yet, since I've been doing some house repairs. Also haven't changed the diff or TC fluids yet. The only thing I've done differently with MO over the past few days is, after turning her off for the night, I pop the hood and pop the tranny dipstick cap for a minute to release the pressure. If you've read my posts, you know that the tranny is way overfilled, and when the cap is popped, gurgling/venting happens. I then place the cap back on and do nothing the following morning when firing her up and getting ready to leave. I still let her warm up for 10 minutes, though.

EDIT: I also changed the oil again and added a quart of Lucas heavy duty oil stabilizer. But that shouldn't have any bearing on the tranny. However, it would likely have an impact on the "flooring it" test. In addition, flushing the cooling system again a few days ago after unclogging that oil cooler line might also have played a part in MO performing better than usual during that acceleration test.

 

[Cryogenix1]

From experience, getting the whole float/pump assembly back thru the top opening can be challenging to say the least. I would be worried that something was forced and maybe slightly bent, causing a float issue.

You should not be smelling any gas when the car is parked. Reading that it took two men to remove the retaining ring gives me concern about the reinstall. A square O-ring is usually between the tank and assembly, prone to partially rolling while fiddling with getting the lock ring into proper position. The float/pump assembly needs to be firmly pressed down on the gasket to prevent any movement.

I should've been more clear in my past post about smelling gas. I meant I sometimes would smell gas after I stopped at a store or at the gas station and then stepped outside the car. I never smelled it inside the car or when MO has been parked/stopped for hours. I did smell strong fuel odors from the exhaust this morning after I quickly started, stopped and started the engine again. But I think that was just unburned fuel in the combustion chambers because I turned the engine on, off and on so fast.

As for the fuel gauge issue... The last three tank top-offs produced no venting/gurgling sounds. I discovered it's not putting on mileage that finally makes the fuel needle go to F, it's duration. I did a few tests, and the bottom line is, if I just let MO sit and idle for 17 minutes, the needle slowly makes it way to F to provide an accurate reading. Braking hard or doing crazy manuevers to try to move the float around had zero impact. So, not sure what that means, but it seems fairly consistent. Note: if I top off the tank, then shut MO down for 17 minutes and restart, the fuel gauge is still wrong. It requires the engine be running for 17 minutes after topping off for the gauge to read correctly.

 

[I need coffee]

Shortly after this post, I added a pint of Marvel Mystery Oil to my fuel, and since then I have not been able to produce the P0172 code when trying to. The only code I threw was yesterday when I tried something that PaulDay suggested in a different thread, about flooring the gas pedal and keeping it pinned to test the CVT. I did that for about seven seconds before I chickened out, and the CVT did fine and transitioned fine and the engine didn't choke or sputter or hesitate. About 20 minutes later, as usual, I threw P0420. It usually happens if the RPMs exceed 3000 for more than five seconds. However, in most cases the engine sputtered and the cruise control's set light would start to blink. During yesterday's "pedal to the metal" test, everything was very smooth and normal. Definitely feel the old fuel pump was making the engine choke by not supplying adequate fuel upon higher demand. The fuel trims look fine to me, especially given the age and mileage of the engine and most of its support components.

-10.2 on both banks is too rich. Also, is the O2 sensor data captured just sitting at idle? Do the upstream and downstream sensors closely follow each other? If your scan tool is capable, I'd be curious to see a merged graph for O2B1S1 and O2B1S2 as well as a graph for O2B2S1 and O2B2S2.

 

[PaulDay]

The only code I threw was yesterday when I tried something that PaulDay suggested in a different thread, about flooring the gas pedal and keeping it pinned to test the CVT. I did that for about seven seconds before I chickened out, and the CVT did fine and transitioned fine and the engine didn't choke or sputter or hesitate. About 20 minutes later, as usual, I threw P0420.

P0420 is an indication of a bad/plugged cat. under those conditions. An oxygen sensor is overheating, usually due to the cat honeycomb being plugged and being hotter then normal.

Good luck.

Have a good day.

 

[Cryogenix1]

P0420 is an indication of a bad/plugged cat. under those conditions. An oxygen sensor is overheating, usually due to the cat honeycomb being plugged and being hotter then normal.

As I've said before, it's because of the clogged CATs that I regularly use lacquer thinner and do other things to try to free up the clogs in order to drive normally and pass annual emissions inspection and keep P0420/P0430 at bay. I only throw those codes when trying to drive aggressively. It's worked beautifully for close to five years (only causing one 17-year-old heated O2 sensor to burn out last Spring - bank 1 sensor 2, I believe) and my MPG has been fantastic at 20/24, but naturally the time will come when things will come to a head and the CATs will either cause the engine/car to run so poorly that everything will have to be replaced (by someone else) or one or both CATs will explode and that crap will get sucked into the engine and kill it.

Only 12,500 miles to go... I wonder how well MO would float?

 

[Cryogenix1]

-10.2 on both banks is too rich. Also, is the O2 sensor data captured just sitting at idle? Do the upstream and downstream sensors closely follow each other? If your scan tool is capable, I'd be curious to see a merged graph for O2B1S1 and O2B1S2 as well as a graph for O2B2S1 and O2B2S2.

Yeah, she's running a little rich and has been for while, but those numbers aren't excessive or really unusual, as far as I'm concerned.. MPGs went down a little since installing the new fuel pump. Probably due to MO now getting more fuel than before (since it seems the old pump wasn't fully doing its job) but could also be because of the colder outdoor temps and the fact that I'm idling longer at places to keep the heat running...plus I'm going a little heavier on the pedal since MO seems to be driving better with that new fuel pump... The only thing I haven't tried yet is dropping MO into Ds and flooring it...

I think those O2 readings are when I was stopped and in P. But I did a few readings while stopped in D, to put a load on the engine. Don't remember which is which, though. Here's the video of it. I really should upgrade to a decent scanner. I bought this piece of junk years ago just to keep clearing the codes as I was trying to clear the CATs.

 

[I need coffee]

What PaulDay said is basically where I was going with all that. A clogged cat (or any exhaust obstruction) can result in a rich condition since the engine can't "breath" as well as it should. But, at this point no sense in doing anything about it. Watch, your Mo is going to spite you and croak at 299,999 miles.

 

[Cryogenix1]

Watch, your Mo is going to spite you and croak at 299,999 miles.

I was thinking of that kiddingly the other day. March 2021 should be D-Day. If my timing is right, MO will be around 299,300 heading into the annual inspection. If I can't get I/M Readiness by then, I'll have to secure an F-Pace and drive MO until 300,000, then donate her.

 

[J5ingh]

Yes, I'm aware that Castrol has actual "CVT" fluid. Since I've taken care of my car and Nissan's CVTs kept failing, and because I was now footing the bill for that used CVT, I wanted to try something different, so I went with Dex6 (per Nissan's original specs) and have had very good luck with it. This is the longest my MO has ever gone without needing a new tranny, so clearly something is working. 158,000 miles using Dex6, and the tranny is still running smooth...I'd say that's not simply luck.

EDIT: however, to be fair, it's possible the Dex6 is the reason I'm getting that P1778 code for the valve body. Perhaps if I had used the "correct" fluid, that code would never have appeared. But, 158,000 miles on a used tranny that supposedly already had 120,00 miles on it is pretty damned good. Even if I have to buy another used one for $1,200 in a few months, I'd say I was doing better than most.

I have a 2005 Murano with 229000 miles. I am the original owner of this car. At about 9500 miles, Nissan Dealer in VA replaces my Transmission for a recall. I change CVT oil every year by dropping the pan. Whatever I get out the same amount I put back in. I buy Transmission oil from the dealer. So far, it's working fine. The only thing which worries me sometimes when I am slowing down right under 20 mile. When the gear change, it's not smooth. But that has been there from the very beginning to some extend.

 

[MuranoSL2003]

I have a 2005 Murano with 229000 miles. I am the original owner of this car. At about 9500 miles, Nissan Dealer in VA replaces my Transmission for a recall. I change CVT oil every year by dropping the pan. Whatever I get out the same amount I put back in. I buy Transmission oil from the dealer. So far, it's working fine. The only thing which worries me sometimes when I am slowing down right under 20 mile. When the gear change, it's not smooth. But that has been there from the very beginning to some extend.

It's normal for your 1st gen Murano to feel a slight to moderate lurch when slowing down through ~20 MPH. It's the torque converter unlocking. My '03 also did this since it was new and for the 16 years I owned it... Congrats for the 229k miles you've gotten from it so far!

 

[Cryogenix1]

Re the new fuel pump giving inaccurate fuel level readings... I could live with the fuel gauge being a little inaccurate if the float were merely sticking and then being fine later on. But, this morning, the gauge read 1/3 remaining before I filled up, and I pre-paid the cashier $40, expecting the tank would take about $33. It took the entire $40 with room to spare. I started the car, the needle edged to 3/4 full... I went and parked on a level surface and kept the car running, and was working on my laptop for about 10 ten minutes. When I looked at the fuel gauge again it had dropped to below 1/4 remaining in the tank. I then watched as the needle dropped to E and the orange fuel pump dummy light came on. I turned off the car, started it up and it stayed pinned at E with the light on. I did that a few more times with no change. Though 99.999% unlikely, I looked under the car in case the bottom of the gas tank had fallen out and dumped fuel everywhere. Nope. I then drove around for another five minutes and it stayed at E, and I decided I couldn't live with that kind of fuel-reporting problem, so I drove another five minutes to the autoshop that installed it. As soon as I got there and turned off the car and turned it back on again, the needle shot to F and stayed there.

In any case, I can understand a stuck float not reading correctly until it unsticks, but I'm not grasping how it can under-report fuel to that extent. As I left the autoshop and drove around, I could see the needle keep shifting slightly from F to just below F and then back to F. When I stopped to do some shopping, I started up MO and the gauge read a little above 3/4 full, and then before leaving the parking lot it edged to F. It sounds like a float problem but then it seems like a problem with a sensor perhaps intermittently losing power or getting low current or something which is sending a weak signal to the fuel gauge. The tech offered to replace the pump next week, but I'm still concerned about leaving my car with that garage again... Always concerned about bad blood and subsequent retaliation against my car that may create a problem down the road. I might just buy that $50 pump online and do it myself.

 

[I need coffee]

Re the new fuel pump giving inaccurate fuel level readings... I could live with the fuel gauge being a little inaccurate if the float were merely sticking and then being fine later on. But, this morning, the gauge read 1/3 remaining before I filled up, and I pre-paid the cashier $40, expecting the tank would take about $33. It took the entire $40 with room to spare. I started the car, the needle edged to 3/4 full... I went and parked on a level surface and kept the car running, and was working on my laptop for about 10 ten minutes. When I looked at the fuel gauge again it had dropped to below 1/4 remaining in the tank. I then watched as the needle dropped to E and the orange fuel pump dummy light came on. I turned off the car, started it up and it stayed pinned at E with the light on. I did that a few more times with no change. Though 99.999% unlikely, I looked under the car in case the bottom of the gas tank had fallen out and dumped fuel everywhere. Nope. I then drove around for another five minutes and it stayed at E, and I decided I couldn't live with that kind of fuel-reporting problem, so I drove another five minutes to the autoshop that installed it. As soon as I got there and turned off the car and turned it back on again, the needle shot to F and stayed there.

In any case, I can understand a stuck float not reading correctly until it unsticks, but I'm not grasping how it can under-report fuel to that extent. As I left the autoshop and drove around, I could see the needle keep shifting slightly from F to just below F and then back to F. When I stopped to do some shopping, I started up MO and the gauge read a little above 3/4 full, and then before leaving the parking lot it edged to F. It sounds like a float problem but then it seems like a problem with a sensor perhaps intermittently losing power or getting low current or something which is sending a weak signal to the fuel gauge. If the float was sometimes sliding freely up and down on its metal rod, I still don't see how it could do what it's doing. And if that metal rod was sliding freely within whatever arm/hole it's secured in, I still don't see how that would create the problems I'm having. I'm guessing the sending unit (or whatever it is) within the fuel pump may be faulty and is getting worse as time goes on. The tech offered to replace the pump next week, but I'm still concerned about leaving my car with that garage again... Always concerned about bad blood and subsequent retaliation against my car that may create a problem down the road. I might just buy that $50 pump online and do it myself.

Based on your earlier posts, your plan is to get rid of the car in a couple of months when you hit 300k miles so why bother putting any more money into it. Just fill up the tank and set your trip odometer to 0.0 and you'll have a good idea of how much range you have left if the fuel needle keeps acting buggy.

 

[Cryogenix1]

Based on your earlier posts, your plan is to get rid of the car in a couple of months when you hit 300k miles so why bother putting any more money into it. Just fill up the tank and set your trip odometer to 0.0 and you'll have a good idea of how much range you have left if the fuel needle keeps acting buggy.

I'll be driving MO for at least another few months and I really don't like looking at the "no fuel" light being on. If it stays off, great...I guess I could always pull a fuse if it's isolated, but I doubt it is. If the needle hadn't dropped to E after filling up, I really wouldn't care about this glitch - I always use the trip set anyway to see how far I go, and to generally see how far I can go on a tank of gas. It comes down to just being curious as to why the fuel reading is acting so spordically. Again, I could understand it under-reporting fuel if stuck and the needle shows 3/4 when it's should show F. But how, when stopped doing nothing, does it go from 3/4 to E? That's what I'm not grasping. Could it actually be the fuel gauge that's crapping out? I like finding answers.