Engine bucking while driving

Cars have many computers these days. Transmission fault codes are generally stored in a different computer than the engine codes.

Automatic transmissions (even CVT’s) are sort of a hydraulic-controlled computer. Fluid pressure places a force on an actuator, which causes something to move to effect the shift operation. The valve body has complicated looking arrangement of channels for the fluid to flow through, and valves which direct it in the desired path. If the valves stick or the seals leak, it won’t allow the high pressures to build up needed to create the large forces to cause the shifting operation. Newer automatics like yours use some electrical-operated solenoid valve, screw into valve body, sometimes the problem is just one of those has failed. There are other hydraulic valves, and generally only replaced during transmission overhaul/rebuild.

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It’s possible that he is correct. Because of Nissan’s worst-in-the-industry record of CVT failures, they did eventually grant an extended trans warranty for some of their vehicles.

Is yours covered by that extended warranty? I don’t know, but the Nissan dealership will know. Hopefully the Nissan dealership will be honest with you about the coverage details.

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The CEL is for emissions related issues and uses the OBD-II (On Board Diagnostics) system. Transmission codes are not emissions related and are still stored. A sophisticated scanner can read the transmission codes as well as the OBD-II codes. It looks like you are on your way to a successful repair. If they have the parts, it should be a quick repair. If they have to order them you have the loaner at least. Good luck.

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Not exactly true. Transmission faults can indeed trip the CEL. A simple code reader will just display a generic transmission error code P0700.

A friend owned a Ford Focus with the 6 speed DDCT. This was a very problematic model and was experiencing a lot of problems. His car got a new transmission about every 30,000 miles and he said he drove it like an old woman to try and avoid problems. The original warranty was much less but various class action suits extended the warranty on his car several times in regards to the transmission. I bet this is the case here as the Nissan CVTs were not known for reliability. In his case, the car got another new transmission about 10K before the warranty finally expired. Once he reached the end of the warranty, he sold that car while the transmission was still good.

I like to look at this page when comparing cars. The Juke doesn’t look too horrible. 2016 Nissan Juke Problems, Defects & Complaints

I think this is the year of the Focus my friend owned. Apparently this one doesn’t look so good, especially in regards to the transmission. 2014 Ford Focus Problems, Defects & Complaints

Good afternoon,

So after 12 long weeks, I finally got my car back.

Now I believe I have permanent “flat spots” in my tires.

How would you approach this with the dealership? Shouldn’t a new set of tires be provided, since this “damage” happened while in their custody, during a warranty repair?

The vehicle sat inactive for 12 weeks. When I got the vehicle back, the low tire light was on and the front tires seemed a bit wobbly. I added air and it seemed to improve, but last night the temp dropped below freezing and the wobbling is more enhanced.

I am waiting to hear back from my regular mechanic, if this is something they can quickly take a look at for me, to confirm that is the issue (can’t imagine what else it could be, 3 days prior to the transmission failing the vehicle passed NH state inspection, which includes tires & suspension), before I contact the dealership.

Thanks in advance,
Kristin

No you can’t expect a new set of tires . Just go to a real tire shop and have them balanced .

It’s possible the flat spots on the tires will self-correct just by driving the car. May take a couple months of daily driving though. No actual experience w/this problem however, never parked a car for that long without moving it. Before Corolla forced off the road due to Covid complications I’d sometimes park my truck for a month without using it. Tires would sometimes get flat spots from that, ride a little bumpy/noisy, but those symptoms would go away after a couple of 10-20 mile 30-40 mph drives.

Suggest some extra driving caution until flat spot problem is resolved, handling and braking could be affected. Esp avoid high speeds.

Modern belted radial tires do not have flat spotting issues like the old bias ply tires did decades ago. If they have any flat spots, some driving will correct it. I have cars that sit longer than yours did and never had any persistent issues with the tires- some a couple years even.

What is concerning is the wobbling sensation. A tire low on air can feel that way but so can one that has not been properly mounted. I would have a tire shop do an inspection…

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Balancing or wearing in is not likely going to correct flat spots on the tires. I would be curious as to how those flat spots got there if they were not present when the car changed hands into their possession.
Towed in park? Tires locked because of the transmission during a test drive and skidded? Someone hammered the brakes hard during a high speed run?

It could be near impossible to prove the tires were damaged by anyone in that chain of events since there seems to be a number of dealers with hands on it. You mention adding air but did not mention checking the actual tire pressure. Proper pressure or add air and hope?

The bigger question to me at this point after 3 months is exactly what was done to the car prior to the tire situation. Replaced the transmission or what? New, used, reman?
Those always nagging detail lapses…

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