230k is a lot of miles for a 1st gen Murano.They don't do well with that many miles generally, they become money pits...

It's likely the CVT is at or near its end of life if it's the original CVT.

You can check for error codes via the Android app CVTz50 app. Most code scanners will not read Nissan CVT error codes. You can tray a drain and fill. Ideally drop the pan and inspect for debris, clean the internal mesh filter too. There is also an external filter.

CVTz50 - Apps on Google Play

CVT diagnostics with ELM327 for Nissan-based vehicles

play.google.com

 

I actually do have that app. I'll give it a shot to see if it lets me know anything. Thanks!

 

Glad there are no CVT error codes!

After rereading your initial post, I think it may be the engine air intake duct. Inspect it carefully for holes. It's a common problem with older Muranos, and can lead to poor low rpms performance. I guess if the leak it just right it may make a sound too, although I haven't heard of it mentioned this forum.

 

I'll look into it.

It's hard to describe the issue. Granted I didn't have this car new but doesn't seem like I get performance loss or any other real issues just the noise and the jerk/pull sensation here and there mainly at the lower rpm or perhaps that's the only time I can hear it. if I have anything else on like the radio or something I can't make out the noise but the noise does coincide with the hesitation/hiccup/jerk/pull that does happen at times.

 

Maybe try and watch the various charts you can pull up in the app. You should be able to see something that corresponds to the jerky behavior you're feeling. Things like rpm and torque produced must be sensing what you're feeling. And hopefully you can work your way toward things like slip and primary and secondary pressure that are related to the transmission to confirm if your cvt is in good working order or might be the source of your jerky feeling. Not sure if you can monitory anything about the awd commanded % in 1ste gen to see if the jerk is related to that. If you already have the app you have access to a bunch of info that should be able to point you in the general direction of your problem.

You can also get one of many free apps that will read more engine parameters than the cvtz50 app to debug in that direction. Like looking at accelerator pedal position sensors (multiple) and commanded and measured throttle position etc. If I were looking for a weird performance problem, I'd be poking at all those data PIDs and trying to see what's going on in the car.

 

You can also get one of many free apps that will read more engine parameters than the cvtz50 app to debug in that direction. Like looking at accelerator pedal position sensors (multiple) and commanded and measured throttle position etc. If I were looking for a weird performance problem, I'd be poking at all those data PIDs and trying to see what's going on in the car.

In terms of apps aside from cvtz50 what would be the recommendation? I guess maybe torque I'll check that out for pids and such. was driving today and using cvtz50 and the cvt fluid ran hot most of the time was stuck in traffic for a bit but yeah. attaching a screenshot. I'm guessing I probably should at least replace the ns2 fluid in there. Does the filter really need to be replaced because that would involve dropping the pan

 

In one of your snapshots, the coolant temperature hit 214 F. That's high. Cooling fans should come on at 208 F and have no problem bringing temperature back down to 199 F where they turn off. If engine is running hot then the transmission will too. I would start looking at the cooling system and functioning of the cooling fans.

 

Thanks, i'll look to see if the cooling fans kick in. I hope I did not mess anything up. Backstory: When I got this vehicle the original radiator's nipple to the reservoir was broken off (there was a screw in its place to keep the coolant in). I decided to order an OEM radiator but I decided to flush the coolant system a few times using one of those cleaners and distilled water. i flushed maybe 5-6 times and the water still looked dirty/bad. I put the new radiator in and filled that up. When trying to purge the system of the air I used one of those Listel funnel things but i noticed as time went on the water/coolant kept rising and rising and had to turn off the car before it shot out of the funnel. checked everything and kept trying and still it kept trying to come out of the funnel. Now, I'm not sure if there is a clog or anything but on my other cars when I do this it bleeds the system of air but the coolant never rises back up. I wasn't getting cool air so my mechanic friend recommended I drive the car onto a hill and rev the engine for a bit to see if I got cool air and I did. Driving it one day shortly after the temp gauge started to rise. Pulled the car over and discovered the hose to the thermostat housing was shooting out the coolant. the hose didn't burst it was just the coolant was bursting out of the seams. Got home pulled the thermostat housing and tested the thermostat seemed like it was working but decided to just buy a new OEM Nissan thermostat with housing. installed it and since then no more bursting out of the seams but I honestly can't tell if the coolant is passing through the system. The temp gauge doesn't rise it always stays right below the halfway mark the coolant in the reservoir will shift from full/close to full/ empty and repeat depending on when I look at it. perhaps the thermostat housing is still not opening and the coolant isn't circulating and just like with the Listel it has nowhere else to go but back up which would be the reservoir.

 

Sigh, I don't think I can activate the test mode. I removed the stock head unit and have an aftermarket one with the Metra 99-7612. Which wouldn't have the preset #4 button or a volume knob. I can get the maintenance menu but not the diagnostic one. All I need to do is to check if the fan works when putting on the AC hot or cold it does come on. but I guess for this instance we want to make sure it's coming on when the cvt/engine is getting hot I take it? I guess it's the worst-case scenario if I need it. I can reinstall the original to test if there's no other way.

To my knowledge, I don't believe a stop leak was put into the system but hard to tell when I got it I could tell the coolant had exploded out but that makes sense since initially, the nipple on the radiator broke off.

Thinking about it inside the hoses it was pretty reddish in coloring, not sure if that was red coolant or a stop leak. but i can try doing another coolant flush not sure if i had the fans on low when I had the heat up high.

 

@igbeserk i like the Car Scanner ELM OBD2 app. It's free and can monitor quite a few data PIDs for the Murano but there are many apps that do the same thing. Like you might monitor the air flow volume and see if the data makes sense or it might indicate you have a leak in the intake tube if your metered air is strangely low. If your fuel trims are way off it might indicate air leaks as well.

You can chart those values like coolant temp and cvt temp in cvtz50 or car scanner so you can get an idea how they trend over time. If you press on one of the data values in the cvtz50 screen it will pop up a chart. Car scanner let's you data log and chart more than one variable at a time. cvtz50 says it can data log but I can't get it to work on my tablet. A chart might be useful to see how high your coolant temp peaks and then you SHOULD see the temp start to fall when the fans kick on and then eventually start to rise again when they turn off (i'll attach a chart i made today at the end of this post). How hot is it where you live? Right now where I live in the northeast US daytime temps are typically ~60F and even though my coolant temp hovers above 200F, my CVT temp is way lower and never gets near 200F. More like 160-170F.

Also, you can activate the auto active test without the screen interface. You read the instructions for the Active Test. Read the section for the Auto Active Test. This just uses the ignition switch and the driver door switch to activate the test. Would be good to be able to confirm your fans can operate and hi and low speeds to eliminate them as a source of your high coolant temps.

If you don't know when your cvt fluid was changed last, I would do that anyway just because it doesn't hurt and then you know its history and who knows maybe it will help with the jerky behavior.

 

@igbeserk i like the Car Scanner ELM OBD2 app. It's free and can monitor quite a few data PIDs for the Murano but there are many apps that do the same thing. Like you might monitor the air flow volume and see if the data makes sense or it might indicate you have a leak in the intake tube if your metered air is strangely low. If your fuel trims are way off it might indicate air leaks as well.

You can chart those values like coolant temp and cvt temp in cvtz50 or car scanner so you can get an idea how they trend over time. If you press on one of the data values in the cvtz50 screen it will pop up a chart. Car scanner let's you data log and chart more than one variable at a time. cvtz50 says it can data log but I can't get it to work on my tablet. A chart might be useful to see how high your coolant temp peaks and then you SHOULD see the temp start to fall when the fans kick on and then eventually start to rise again when they turn off (i'll attach a chart i made today at the end of this post). How hot is it where you live? Right now where I live in the northeast US daytime temps are typically ~60F and even though my coolant temp hovers above 200F, my CVT temp is way lower and never gets near 200F. More like 160-170F.

Also, you can activate the auto active test without the screen interface. You read the instructions for the Active Test. Read the section for the Auto Active Test. This just uses the ignition switch and the driver door switch to activate the test. Would be good to be able to confirm your fans can operate and hi and low speeds to eliminate them as a source of your high coolant temps.

If you don't know when your cvt fluid was changed last, I would do that anyway just because it doesn't hurt and then you know its history and who knows maybe it will help with the jerky behavior.

View attachment 57341

Awesome thanks for the response. i'll look at the document again maybe i missed the part about how to engage it. and yesterday it was up to 80 degrees F if i recall but lately, its been around 60-70F i'll try those settings and that app and those other recommendations. thanks! also just do a change i guess and not worry about the transmission filter etc? I actually have a few quarts laying around of the Aisin ns2 fluid guess i can use that.

 

Ugh, I'm an idiot sorry I really needed to read that pdf. ran the diagnostics, everything worked, coolant fans came on low and high, ac clutch clicked, wipers etc. so, all that seems to be good.

So, essentially next steps monitor the data, perhaps try to flush out the coolant again and also might as well replace the trans fluid and then reset the deterioration on it.

 

Just drive it and log some data. See what you can find that looks interesting when the jerky feeling occurs. Might not be related to coolant temps or transmission at all. Could still be air leaks or who knows what. More data will help you focus in the right direction and waste less time on stuff that might be good to do but isn't really related to your problem. Honestly that description of a horn sound sounds more like an air issue. Like if you pass air over a reed (or a crack in the fold of the intake tube) it can make a vibrating horn noise. I'd be looking at that intake tube if you haven't already before I messed with the coolant or the cvt fluid. It's free and relatively easy compared to those other jobs. That's just based on the description of the symptom sound and a little off the description of the driving behavior. That plastic is old and it lives in a terrible environment. We're lucky they last as long as they do.

 

I tried bleeding the coolant again, and after roughly 30 minutes or so it started to gush out. I put the Murano up on ramps and I just wanted to confirm so i should have the heat all the way up and the fan set to 1 and should it be AC on or AC off? I tried a few combinations towards the end i had the fans all the way up and I was revving at around 2000 rpms for a few minutes but prior to doing this my vents weren't blowing out hot air only mildly warm air until i started revving and then looking at the funnel i see it about to gush out so i turned off the engine. I guess there's still stuff from whatever was in the system like a reddish rust look. I used the prestone concentrated with distilled water 50/50. It should be a bright green color not this dirty reddish tint to it.

 

If that "reddish" tint is the previous coolant, I would totally purge that cooling system, flush it thoroughly and start over with green coolant. Mixing types of antifreeze is very bad news and can cause deposits which clog the radiator. There are different colored types of antifreeze for a reason, and some of them do not mix.

 

yea, seems like I'll have to change the coolant again. I've flushed it like 6-7 times months ago but that's not the color of the coolant i put in so yea. i'll give that a shot this weekend. thanks!

 

I had a tough time with my cooling system when I bought my 2010 earlier this year. I replaced a leaking radiator and couldn't get proper heat from my vents. I ended up having to flush my heater core directly because it doesn't really get flushed forcefully enough with a basic cooling system drain and fill. If you've run your engine for 30m with a spill-free funnel connected and you still don't get HOT air from the vents, I'll bet your heater core is partially clogged like mine. I flushed mine into a bucket and posted pictures of the sediment that came out of it. It's much better now but probably not perfectly clean. I documented the air temp coming from my vents before/after the heater core flush and compared to my other vehicles. I included some pictures of where I disconnected the heater hoses because it's too hard to do it at the firewall.

https://www.nissanmurano.org/threads/clunk-bang-when-accelerating-from-stop-cvt-or-motor-mount-and-other-stuff.227640/#post-777694

Sounds like you're doing it right to me. I don't understand why the coolant would want to gush out if you were only revving to 2000. Mine would sort of percolate in the funnel a bit but barely splash out and I revved it significantly higher than 2000. Your cooling fans should cycle to keep things in a normal temperature range and the coolant will only expand so much. If you just stopped revving the engine (not shut it off) I would imagine it would not continue to gush out if everything is normal.

 

The liquid in that funnel looks like orange juice and it appears to be boiling. The vents not blowing hot air with the heat on while bleeding the system suggests air pockets in the heater core. I would suggest disconnecting the heater hoses and running water through the heater core to see how it flows to rule out a possible obstruction within or just do a force flush as @jbarnett250 suggested. If that checks out o.k. then possibly proceed with more system flushing, but it seems like there may be a flow problem somewhere.

 

Going to do the force flush, b any chance any of y'all know the Inner Diameter hose I'd need for the heater core? I saw in @jbarnett250 post he used a 3/4ID but it also doesn't seem like he did it directly at the HC. Also, he has a 2010 not sure if it'd be the same exact as a 2007. Thanks.

 

I drained the radiator and I was able to get a hose connected and flush out the heater core definitely a lot of stuff came out. I tried to fill the heater core with coolant after the flush but was unable to. I connected everything back together and added coolant and it seemed to fill up with less fluid than I remember. Started the car and when I revved the engine I couldn't rev past 1500rpms had no power and I got a few dtc codes that came in P0221/P0123 and P0223 if I recall. Didn't have time to asses much will check tomorrow. Anyway trying to purge the system of air the coolant eventually shot out through the funnel. I guess my biggest worry right now is we will probably get freezing temps tonight and the heater core has water in it. GG

 

That's interesting. Those codes are related to the accelerator pedal and throttle position sensors. That's definitely the kind of thing you can monitor with your obd interface. You can monitor both accel pedal sensors and the commanded throttle position and the measured throttle position to see what doesn't match up right. If something doesn't correlate, the car isn't certain where your foot is or where the throttle plate is which is a bad thing. I wonder if the jerky behavior you felt was originally related to the pedal/throttle issue?

As far as filling the cooling system after the heater core flush, I couldn't fill the heater core directly with coolant without making a huge mess so I didn't even try. I blew as much of the tap water out of the core as I could with my lungs. Then reattached the hoses, then filled the cooling system like normal. I forget if it was the manual or a diy I read that said to fill it really slowly (like 1 gal/min) to avoid trapping more air. I recall needing about 2 gallons of coolant to fill my system and reservoir. after the flush. I don't understand why there's so much pressure in your cooling system that it can shoot out if there's nothing to contain the pressure like a radiator cap. Hopefully you had enough coolant in the system to avoid a freeze up. That wouldn't be good.

 

Started the car and when I revved the engine I couldn't rev past 1500rpms had no power and I got a few dtc codes that came in P0221/P0123 and P0223 if I recall.

Those are all throttle position sensor codes. If you unplugged it, did you make sure to plug it back in?

I drained the radiator and I was able to get a hose connected and flush out the heater core definitely a lot of stuff came out. I tried to fill the heater core with coolant after the flush but was unable to. I connected everything back together and added coolant and it seemed to fill up with less fluid than I remember.

If there was a lot of "stuff" in the heater core then that stuff has probably made its way to other parts of the cooling system. Did debris come out of the radiator when you drained it? If so, try disconnecting upper and lower hoses from the radiator and do the same hose flush through the top of the radiator and see if a lot of junk comes out too.

BTW, what does this debris look like? If you really have that much garbage circulating through the cooling system, I'd be tempted to pull the thermostat and see if it's loaded with crap that might be restricting flow through it (...might require a new gasket). Below is a schematic of how the coolant flows through the system and it goes from cylinder head -> radiator -> thermostat -> water pump so if the thermostat is gunked up then that may explain why the coolant level is rising so high and so quickly in the funnel. It could also possibly explain the gushing when revving the engine if the water pump is trying to push coolant into the radiator at high volume but it can't flow quickly enough through the thermostat so the excess pressure gets vented out the radiator neck into the funnel. Just a theory, FWIW.

 

Those are all throttle position sensor codes. If you unplugged it, did you make sure to plug it back in?

Yep, i did plug it all back and checked. I probably should have disconnected the battery. I forgot with Nissan there's a lot of idle relearn and other things. i'll try pulling the thermostat to see how it's looking i believe that's easy and i'll try to flush out the radiator directly. i did take a pic just forgot to add it.

 

Regarding air pockets. I heard that Infinit V6 engines have a reputation for being difficult to burp the air out of the heater core. Same engine as us I believe. The method he mentioned was they vacuum the cooling system of air, then suck in the coolant. Sounds effective, but I don't think it's a DIY type of thing...

But in this thread, it's crud gumming up the system that is causing the issue...

 

Looks like I'm going to need a new therm

ostat

 

That is the coolant temperature sensor. But, yes, that's broken.

Thermostat is on the cylinder head near where the serpentine belts are. You said you replaced that, correct?

 

Yes sorry it is the coolant temp sensor and yes I replaced the thermostat with the housing and the gasket OEM from Nissan like 3 months ago. And the throttle body was disconnected

 

Yes sorry it is the coolant temp sensor and yes I replaced the thermostat with the housing and the gasket OEM from Nissan like 3 months ago. And the throttle body was disconnected

O.K. That's what I meant about pulling the thermostat housing and seeing if there's gunk in there too.

Were the cooling fans coming on at all while bleeding the system?

 

If you saw gunk around the thermostat and red flakes, I am concerned that there are deposits which are limiting the amount of cooling. Given the red flakes, I'm wondering if there were incompatible types of antifreeze used in that engine, causing deposits.

 

Maybe or improper care to it. I just connected a hose which heads towards the heater core I left the radiator drain plug off and the bottom hose disconnected. Water was coming out of both locations and water was coming out of the thermostat housing hose as well

 

Alright tried flushing it again with the coolant flush system and distilled water. Think still clogs somewhere. Reservoir was about to fill to the top. So not sure what else to do or try and still have loss of power and throttle body is connected again.

 

I'm struggling for ideas. I'm also wondering if the radiator is flowing OK.

Have you tried disconnecting the top and bottom hoses and running water through the radiator to see if it's flowing OK?

 

I haven't tried that I can give it a shot. I'll try it tomorrow. think my biggest concern was not leaving water in the system to potentially freeze overnight. I still have possibly 2 more hours of daylight but I can start it early tomorrow.

I was able to bleed the system of all liquids I believe. I used those coolant service kits and used my data vac (pushes and sucks air) to the hose connector on the coolant service kit and essentially watched all the liquid shoot out of the bottom of the radiator until there wasn't any. I set it up so it should have started at the heater core first. but I will try to see if the radiator is flowing properly tomorrow.

If the radiator is not flowing properly then I should replace it or just try to fix its flow issue I guess first.

And thank you all for all your help so far. my biggest worry was leaving water in the system so since that's gone i can let it sit for a bit if i need to.

my mechanic friend linked me to this kit Amazon.com: Coolant Vacuum Refill Kit Time-saving&Well-sealed Cooling System Vacuum Purge & Refill Kit with Accurate Pressure Gauge, 4 Sizes of Adapters, Brass Connector,Long Coolant Filling Hose for All Vehicles : Automotive

Said i can give it a shot, should essentially suck the air out and force the coolant in so i don't have to bleed it.

 

That's a good sign that it wasn't all gunked up. At least you now know that it is not the cause of an obstruction. Also a great idea to boil it to be sure it's opening correctly. Sorry you had to deal with again...

 

I agree with all points here. I also agree that the radiator is likely to be OK.

 

Yep, it operated fine when i boiled it. I also ran water through the system again just to make sure and it did come out of the thermostat area. Surprisingly it wasn't as hard to remove/reinstall as it was before. Fingers must've gotten thinner lol. I put some more distilled water and one of those cooling flush system kits from prestone and ran it for 25 minutes. The funnel kit I got isn't working well, it doesn't create a proper seal with the cap. so I capped the radiator and left the reservoir cap off. (not sure if that changes anything) let it run for 25 or so minutes had to rev it to get hot air to come out, the fan kicked on here and there, and also tried with AC on and off. the water didn't seem to rise from the reservoir. Not sure if that means the issue has been resolved I doubt it. Going to dump the water out and use the vac to blow out all the remaining water in the system. The coolant kit comes in tomorrow that should create a vacuum to suck out all the air and let the coolant flow in. so i'll refill with the 50/50 when the kit comes in tomorrow. Any recommendations on what coolant I should use? I've been doing 50/50 with the Prestone concentrate Prestone All Vehicles - 10yr/300k Mi- Antifreeze+Coolant (1 Gal - Concentrate) - Walmart.com