New member with Primera WP12 QR20 CVT

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   Hello again.
I bought this car because the caravan and petrol suited me.
But I didn't know that there were no mechanics for this car near me. They know nothing about Nissan cars and even less about cvt gearboxes.
I have a problem and I can't solve it alone. I stumbled to fix this car and I don't want to sell it.
The car was repaired by 4 different mechanics for more than 2 months and they did not repair it. He had several errors that he reported and none of them were fixed.

I started fixing it myself. I've fixed a lot of things. He had error P0031 Oxigen sensor 1. The mechanics took off my original Lambda probe and put in one that is not good. The error disappeared, but the car spent a lot of gas and not worked poorly.
I don't have the original sensor to see the number, so I put the lower sensor on the upper place and I put the bad one from the upper to the lower place and enabled the car to drive good.

I ordered a new universal lambda sensor NGK so I will try to put it as the first Oxygen sensor and put the existing second original back in place. That way, I may reduce consumption even more, because it is now 9L in the open and 15.5L in the city.
I currently have a problem with error P1791
I'm not sure what that is. Somewhere I read that it is a sensor of oil pressure in the transmission and somewhere that it is a step engine in the transmission.

P1791 can be reset and reappears with car start.
A couple of days ago I drove the car to the highway to try the car I drove very short and some more errors occurred and the car lost power. I barely got home.
P1720 vehicle speed sensor output
which caused both of these
P1574
P1777
I immediately tried to undo the errors but failed. I even turned off the battery and nothing. I tried it several times and nothing. When I got home I left the car for a couple of hours and didn’t start it. When I turned it on again I only had error P1791 there were no other errors.
It would mean to me that someone tells me exactly what the problem is so that I can replace it.

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Vučko Members Profile Send Private Message Find Members Posts Add to Buddy List NPOC Guest Joined: 03 Feb 2022 Location: Bosna Online Status: Points: 6	Post Options Post Reply Quote Vučko Report Post Thanks(0) Quote Reply Topic: New member with Primera WP12 QR20 CVT Posted: 05 Feb 2022 at 3:40pm
	Hello again. I bought this car because the caravan and petrol suited me. But I didn't know that there were no mechanics for this car near me. They know nothing about Nissan cars and even less about cvt gearboxes. I have a problem and I can't solve it alone. I stumbled to fix this car and I don't want to sell it. The car was repaired by 4 different mechanics for more than 2 months and they did not repair it. He had several errors that he reported and none of them were fixed. I started fixing it myself. I've fixed a lot of things. He had error P0031 Oxigen sensor 1. The mechanics took off my original Lambda probe and put in one that is not good. The error disappeared, but the car spent a lot of gas and not worked poorly. I don't have the original sensor to see the number, so I put the lower sensor on the upper place and I put the bad one from the upper to the lower place and enabled the car to drive good. I ordered a new universal lambda sensor NGK so I will try to put it as the first Oxygen sensor and put the existing second original back in place. That way, I may reduce consumption even more, because it is now 9L in the open and 15.5L in the city. I currently have a problem with error P1791 I'm not sure what that is. Somewhere I read that it is a sensor of oil pressure in the transmission and somewhere that it is a step engine in the transmission. P1791 can be reset and reappears with car start. A couple of days ago I drove the car to the highway to try the car I drove very short and some more errors occurred and the car lost power. I barely got home. P1720 vehicle speed sensor output which caused both of these P1574 P1777 I immediately tried to undo the errors but failed. I even turned off the battery and nothing. I tried it several times and nothing. When I got home I left the car for a couple of hours and didn’t start it. When I turned it on again I only had error P1791 there were no other errors. It would mean to me that someone tells me exactly what the problem is so that I can replace it.

imckay Members Profile Send Private Message Find Members Posts Add to Buddy List NPOC Member Joined: 11 Mar 2007 Location: Manchester Online Status: Points: 3374	Post Options Post Reply Quote imckay Report Post Thanks(1) Quote Reply Posted: 05 Feb 2022 at 3:46pm
	Welcome to NPOC Workshop Manuals here https://www.npoc.co.uk/forum/nissan-primera-factory-service-manuals_topic29493.html P1791 is a fault with the CVT Gearbox. Has the Fluid been replaced and if so, was it replaced with Genuine Nissan? NS-2 I think.

Vučko Members Profile Send Private Message Find Members Posts Add to Buddy List NPOC Guest Joined: 03 Feb 2022 Location: Bosna Online Status: Points: 6	Post Options Post Reply Quote Vučko Report Post Thanks(0) Quote Reply Posted: 05 Feb 2022 at 4:17pm
	Valvoline CVT I dropped 6L and poured 6L of Valvoline CVT oil I had neither NS1 nor NS2 oil anywhere to by.

imckay Members Profile Send Private Message Find Members Posts Add to Buddy List NPOC Member Joined: 11 Mar 2007 Location: Manchester Online Status: Points: 3374	Post Options Post Reply Quote imckay Report Post Thanks(0) Quote Reply Posted: 05 Feb 2022 at 6:42pm
	Did you have the P1791 before filling with Valvoline? It looks like Valvoline is Ok to use with Nissan CVT. There have been a few people that have used normal Auto Transmission Fluid. That does not work.

Vučko Members Profile Send Private Message Find Members Posts Add to Buddy List NPOC Guest Joined: 03 Feb 2022 Location: Bosna Online Status: Points: 6	Post Options Post Reply Quote Vučko Report Post Thanks(0) Quote Reply Posted: 05 Feb 2022 at 7:50pm
	Yes. P1791 was before too. i have now looked at this user manual so i am not sure if the stepper motor is causing the problem or the line pressure sensor. the step motor drives the lever coming out of the metal part to which the oil filter is attached. I guess it's a line pressure sensor. That is, there is a sensor within that part.