[scoob5555]

Hi all - we bought a 2009 LE with a lot of miles back in December 2020. Everything was great until it started with the issue of no power from start, especially on hills. I let it go for several months then changed the stepper motor and put in new Idemitsu CVTF Type N fluid (sometime last summer). It worked great for about 9-10 months when it started doing the same thing again. I bought a new kit with all of the solenoids, stepper motor, wiring harness, and sensor and installed them on Saturday. I refilled it with the fluid and tried driving it. It didn't go well. I made it out of our very lightly sloped driveway and onto our flat street. It was accelerating slowly, but I wasn't pushing very hard either - I'm aware that the fluid needs some time to repopulate all of the nooks and crannies in the valve body, etc. I tried to go up a pretty aggressive hill in the neighborhood with no running start and made it about halfway before it shuddered hard and stopped moving forward. The rpms wouldn't go above ~2000. I had to back down the hill and then it stopped altogether. No reverse at all and any forward movement was in the wrong direction so I parked it and towed it back to the house.

Yesterday, I went back in and swapped out the new parts for the old stuff, except for the stepper motor. I refilled it and let it sit for a few hours before trying it. It went slowly enough that I didn't even attempt to play with the hills and went right back home. I waited a few hours and tried again and this time it was way better, but still no real acceleration on the low end. I was able to drive all of the neighborhood hills but was losing speed on all of them. I went out onto surrounding roads and was able to get up to 45 mph but I didn't seem to have either the low side or the high side when accelerating - the motor would rev up but the transmission wasn't translating it into higher speeds.

Again I waited for another few hours and tried again but it was the same as the previous attempt - no good acceleration and no speeds above 45 or so. As it stands, we can make it out of the neighborhood but I'm not too confident that it'll make it back. Any suggestions on what else to try to fix? I'll run the codes tonight - the tablet wasn't charged yesterday.

 

[chidog]

Most importantly what are the fluid pressures? All automatic and CVT transmissions need the high fluid pressures to work correctly. Just knowing the (main) line pressure will be a huge help.
It could also be suffering from the broken and messed up variator guide ball syndrome. There can be issues with valves hanging up in the valve body, I suppose that is the next step before removing the transmission. Keep us posted on what happens.

 

[scoob5555]

Codes from CVTz50:
P0715 Input Spd Sen/Circ
P0705 PNP Sw/Circ
P1777 Step Motor Circ
P0746 PRS Cnt Sol/A Fctn
P1778 Step Motor Fnc
P0868 Sec/Press down

I cleared everything and drove but no change and then they all came back again.

 

[scoob5555]

From Torque Pro, I have
P0705 Powertrain transmission range sensor circuit malfunction
P0171 Powertrain system too lean (bank 1)

 

[chidog]

P0705 could be since you would have played with the connectors maybe something not cool there. Lean code is engine related. PCV ?
The P0868 is the tell tail flow control valve failure code in these transmissions, yes other things can cause it but that is the biggy.
High miles on it and P0868 I say the transmission needs to come out. Have to take off the bellhousing to remove the pump and flow control valve. On REOFO9A Jatco CVT.
And one more thing to try is make sure all ground connections are good and clean from battery down to frame and transmission.

 

[Grav]

Codes from CVTz50:
P0715 Input Spd Sen/Circ
P0705 PNP Sw/Circ
P1777 Step Motor Circ
P0746 PRS Cnt Sol/A Fctn
P1778 Step Motor Fnc
P0868 Sec/Press down

I cleared everything and drove but no change and then they all came back again.

Solution - Disconnect and reinstall the Transmission Speed Sensor and also ensure it is an OEM or Nissan Sensor.

I had a very similar issue on a '06 with the ODB Code P0715 showing initially and after driving a few more days, the rest of the codes started popping up. Even though it's a different model the issue is looks very similar.

Nissan Engine Control Modules and Transmission Control Modules will not fully accept Sensors from other manufacturers be cause of differences in ohms or resistance, voltages or signal frequencies.

Issues went away after using a Nissan Speed Sensor

 

[scoob5555]

Thanks, Grav. I'll give this one last shot. Ordered the sensor and it'll be here Sunday. If that doesn't work I'll sell this one for parts and get something that's literally anything but a Nissan (with a CVT).

 

[Costee]

Thanks, Grav. I'll give this one last shot. Ordered the sensor and it'll be here Sunday. If that doesn't work I'll sell this one for parts and get something that's literally anything but a Nissan (with a CVT).

I'm curious here. P0715 relates more to a malfunctioning TCM (if at all). It's P0720 that requires a sensor. What's the part number of the sensor you ordered? Hopefully, the sensor resolves your issues nonetheless.

 

[scoob5555]

No dice on this one, either. I’m done - car is for sale.

 

[chidog]

I didn't think it would work. Everyone thinks because it fixed their problem it will fix others too.
Did the stepper motor and variator position fork, get engaged properly into the pin on the variator position linkage at both ends?
The P0868 seems to always mean the flow control valve is junk, and it doesn't take much for them to become so. Best thing that may help it is regular fluid changes, but not after the damage is done. I used the Transgo drop in flow control valve, and it seems to work okay so far.
Yeah can't blame you for being sick of the car, it is by far the worse vehicle that I have ever worked on. Nice looking cars, but wow not for a mechanic.
By the way some of the codes could be related to improper engagement of that linkage. Are you sure it is correct? If so then ignore this last sentence.

 

[scoob5555]

Yes, I triple checked the fork on both ends. Can the valve get changed without dropping the whole trans? Thanks

 

[chidog]

I wish it could. If they would have designed it all correctly then yes it would and could be a simple thing to do by just removing the valve body. But not the case that is if you have the same series transmission as a 2004 murano. A quick check looks like it is also a CVT-3. A 2004 has REOFO9A, 2009 mentions a REOFO9B ? Not sure what is different, but basically the same transmission.
I think even on the chain drive fluid pump models the transmission still needs to come out to do the flow control valve. I suppose they design that for a reason like more $ to fix it.
It is a huge pain to remove the transmission, and as long as the variator pulleys look good and belt, there should be no reason to dig any farther than the pump removal to fix a bad flow control valve.
That wouldn't be too bad of a job to do, and pretty minimal parts for the transmission. You could even reuse the pump gasket, that is what was done in the past before kits became available. The input shaft converter o-ring should be new, I would think that is available separate. Kits are available but would be overkill for just the pump.
Oh and the transmission can be removed with out removing the engine or draining the coolant. Having 2 chain hoists helps, one to hold up the engine and the other to lower the transmission. The hassle is all the super tight bolts and rusty exhaust fasteners. I leave the steering rack on the car, just remove the 2 bolts that hold it in the sub frame. Use big wire ties to hold up the tie rods.
Leave all the brakes and knuckles on the struts, just remove from lower ball joint clamp. Anyother way is just unnecessary work. Use a strap to hold it out of the way if needed. And dealing with up and down with sub frame is easier than loosening over tightened bolts, 2 floor jacks help.
Since you have done the things mentioned above, I think you could handle the job just fine. Have some knowledgeable help or any help would be great. The nasty things are the torque converter nuts, very tight and you would not want to round them off. If you decide to do it, I have some suggestions as you proceed.