FaultScore

Infiniti Q50 acceleration problems

46 of the 740 complaints filed about the Infiniti Q50 are about the throttle and cruise control — 6% of everything owners reported. The worst model year for it is 2015.

46

Complaints

6%

Share of all complaints

5

Crashes

0

Fires

Acceleration & Cruise Control complaints by model year

2014 Q50 11 23.9%

Median failure at 53,000 miles

2015 Q50 21 45.7%

Median failure at 56,000 miles

2016 Q50 3 6.5%

Median failure at 18,850 miles

2017 Q50 2 4.3%

Median failure at 6,355 miles

2018 Q50 2 4.3%

Median failure at 8,700 miles

2019 Q50 4 8.7%

Median failure at 2,000 miles

2020 Q50 1 2.2%

Median failure at 10 miles

2021 Q50 1 2.2%
2023 Q50 1 2.2%

What owners said

2015 Infiniti Q50 Dothan, AL

VEHICLE SPEED CONTROL

While driving my 2015 Infiniti Q50s, the transmission suddenly suffered a catastrophic electronic failure, causing the vehicle to immediately drop into "limp mode." This resulted in a sudden and dangerous loss of acceleration while operating in traffic. A diagnostic scan revealed trouble codes P0500 and P0720 (Output Speed Sensor circuit). However, following Infiniti's official Technical Service Bulletin (TSB ITB19-040), the actual failure was the Transmission Control Module (TCM), which is permanently integrated into the transmission control valve body inside the transmission. Because the speed sensor cannot be replaced independently of the integrated module, I was forced to pay out-of-pocket to replace the entire transmission control valve body assembly and have a dealership program the new unit. This is a widely documented, premature failure on this vehicle platform that creates an immediate highway safety hazard when the vehicle drops power without warning.

NHTSA complaint #11750490 — an unverified report by a vehicle owner.

2019 Infiniti Q50 Omaha, NE

VEHICLE SPEED CONTROL

Early turbo failure should be extended to newer vehicles not only up to 2018. I am experiencing turbo failure and there is no extended warranty for this repair.

NHTSA complaint #11749209 — an unverified report by a vehicle owner.

2016 Infiniti Q50 Cedar Hill, TX

VEHICLE SPEED CONTROL

OUTPUT SPEED SENSOR on 2016 INFINITI Q50t - Took vehicle in for oil and filter change 2 days ago. I drove the car about 40 miles, without incident. Went back to same place for state inspection yesterday. I drove about 2 miles from the inspection place and park in shopping lot. Went in business to shop for about 30 minutes. Returned to vehicle and drove about 100 yards through the parking lot. The car appeared to lose power and made a jerking movement as if it didn't want to go. I drove out onto a very busy street and we were almost rear ended by other traffic. I pulled up in another parking lot to assess the problem. I could not determine what was causing the car not to pick up speed. I drove to an AutoZone: battery checked out at 90 percent good; no electrical problems noted either. I drove off about 1 block from AutoZone: the CEL came on for the first time. I went back to the AutoZone to get them to check it out. The diagnosis code is P0720: vehicle speed sensor. I went back to the inspection shop the next day and I was told the same code. I took the vehicle to the dealership and I was told that I need to replace the whole transmission. I purchased the vehicle about 8-1/2 years ago; garage kept; only put 60k miles on car since purchase. Car has approx. 108k miles now. This is not only a problem with 2014 -2015. When I purchased the car in 2018, I feel like the dealership should have informed me that this was a problem with Q50s. This is not just an issue with previous years; this is a problem with 2016 as well. This vehicle is very clean/outstanding: no accidents, no body damage, immaculate leather seats, no repairs in 8-1/2 years and all of a sudden this fault code comes up with no previous indication that the transmission was not working properly. There needs to be a RECALL for this vehicle due to this common issue.

NHTSA complaint #11738665 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Acworth, GA

VEHICLE SPEED CONTROL

The transmission speed sensor has failed needs a new valve body. It seems like a very common problem with this car and it’s a $3000 fix according to my mechanic. I think there needs to be a recall issued considering everybody on this website is reporting the same problems.

NHTSA complaint #11731441 — an unverified report by a vehicle owner.

2014 Infiniti Q50 Columbia, MD

VEHICLE SPEED CONTROL

MY CAR WAS DRIVING ALONG AND ALL OF A SUDDEN THE STEERING WHEEL GOT EXTREMLY TIGHT AND THE CAR WAS HARD TO STEER, I HAD TO PULL OVER TURN THE CAR OFF AND THE LIGHT WAS STILL ON, I WAS LIKE 2 MILES AWAY FROM MY HOUSE, TALKING TO A NEIGHBOR THAT HAS SAME CAR DIFFERENT YEAR, STATED TO CHECK RECALL HIS CALL DID THE SAMETHING YEARS AGO WHEN WE HAD A COLD (LOW TEMPERATURE) WINTER AND IT WAS REPLACED BY INFINITI DEALER. I NEVER HAD ANY ISSUE WITH THIS CAR UNTIL NOW.IT'S BEEN REALLY COLD. ALSO THIS CAR HAS ISSUES WHEN IT RAINS, IT DOESN'T WANT TO START, I HAVE CHECK OUT MANY VIDEOS STATING THE SUNROOF LEAKS OR TUBES FOR SUNROOF GETS CLOGGED AND LEAKS INTO THE BCM OR ECM SYSTEM CAUSES DAMAGE AND DASH LIGHTS. IM NOT A MECHANIC BUT I KNOW THAT THIS IS SOMETHING INFINITI/NISSIAN SHOULD HIGHLY LOOK INTO. JUST A GIRL,BUT I KNOW MULTIPLE PEOPLE SHOULDN'T BE POSTING THE SAME CONCERNS ON THEIR CARS AND IT'S NOT BEING LOOKED INTO

NHTSA complaint #11714276 — an unverified report by a vehicle owner.

2015 Infiniti Q50 North Highlands, CA

VEHICLE SPEED CONTROL

The car just slowed down super fast on freeway almost got rear ended. It would not go past 3rd gear. Poor acceleration. Could have caused a huge accident. I got it diagnosed and they said it is valve body/speed sensor/tcm and they said this is a COMMON problem for 2015 Q50. I replaced this part 2 years ago and here we go again. Shop diagnosed and said this tcm (transmission control module which is in the transmission) but they have to change whole transmission. Everything happened all the sudden then check engine light came on.

NHTSA complaint #11683201 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Temecula, CA

VEHICLE SPEED CONTROL

P07200 code came up, transmission is no good because of a cheap sensor that's impossible to fix. seems to be very common and very inconvenient

NHTSA complaint #11681641 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Houston, TX

VEHICLE SPEED CONTROL

i’m reporting issues with the valve body on a 2015 Q50. I have had to replace the valve body already at cost of $1700. Many others have had same issue as this is a common defect with the TMC part. This needs to be addressed as a recall.

NHTSA complaint #11681660 — an unverified report by a vehicle owner.

2018 Infiniti Q50 Phoenix, AZ

VEHICLE SPEED CONTROL

My car wouldnt start and when it did, it would start shaking and every time I accelerate, The speed wasnt going any faster but only the RPMs were

NHTSA complaint #11681634 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Houston, TX

VEHICLE SPEED CONTROL

Just over 1 week ago, I was leaving a parking lot and driving back to my home when my car wouldn't accelerate past about ~10-15 miles per hour and wasn't shifting gears. When I took my foot off the gas pedal, the gear just dropped immediately from above third to first gear and the car shook. I first noticed this when already out of the parking lot and pulling off from a median onto the road, with no engine light or other warnings. I quickly pulled into the turn lane where there wasn't traffic and turned the car off and back on. It was the same but luckily I was in eyes view of my apartment, so I drove under 10 mph and made it home. I took the vehicle to a transmission service center and the error code that came up on the computer was (P0500 - Vehicle Speed Sensor A), which the service center said is an issue with the "valve body" inside the transmission, specifically the "TCM - Transmission Control Module" that sits on top of the valve body. I contacted multiple Infiniti service centers and they all confirmed that the valve body for my vehicle (part# 31705-x133a) is back ordered by over a month and could be longer until they have it. They do not sell the Transmission Control Module separately. The valve body was quoted to me for $2200 for the part alone. I attempted to install an aftermarket valve body and a new error code came up on the computer (PO720 - Output Speed Sensor Circuit). I kept the original valve body and will hold onto it. Doing some more research, this appears to be a common issue with the Infiniti Q50 - [XXX] In addition to the reddit thread above, a quick google search for Infiniti Error codes P0500 and PO720 point to multiple sources indicating the same common experience and outcome. My vehicle has 110k miles and users in the reddit comments are also reporting the same issue with the TCM Transmission Control Module occurring between 85k - 100k miles in all cases. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11664950 — an unverified report by a vehicle owner.

2023 Infiniti Q50 Suffern, NY

VEHICLE SPEED CONTROL

I’m reporting a recurring safety issue with my Infiniti Q50 involving the brake, steering, and acceleration systems. While driving, I’ve experienced the brake pedal becoming unresponsive, the gas pedal not reacting, and the steering wheel locking or feeling stiff, making it extremely difficult to control the car. The most recent incident occurred today, [XXX]. I had to stop driving immediately and had the car towed to an Infiniti dealership, where a full systems check was performed. However, since the issue didn’t replicate while there, the dealer said they could not determine the cause. The car is available for inspection if needed. The safety risk is severe: I could not stop or accelerate safely, and I struggled to steer — this put me and other drivers in danger of a serious accident. I have experienced this more than once. The dealership originally diagnosed worn brake pads, which I had replaced at an independent shop, but the problem continued afterward. I also showed the dealership photos of the warning symbol that appeared on my dash during both incidents. The car has been inspected by the Infiniti dealer and an independent mechanic, but no resolution has been found. No inspections have been done by police or insurance. Given the serious nature of this malfunction, I am requesting this be investigated as a possible safety defect. Thank you, [XXX] Suffern, NY [XXX] [XXX] Infiniti Q50 2023 INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11660788 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Port Barre, LA

VEHICLE SPEED CONTROL

Transmission, Transmission Valve body, speed sensors. After transmission shifting issues while traveling the interstate I had to have the car towed to the dealership. After the multi point inspection was performed serveral recommended itmes related to the ongoing performance and SAFETY of the vehicle listed below: Transmission $10,446.65 Transmission Valve Body $3693.92 The diagnostic code P0720. Attached is the service bulleting stating they know this will happen and when it does here's how to fix it. Yet they have never recalled the defective transmission. When I contact Infiniti consumer affairs they simply say that they cannot help me because the vehicle does not have warranty. If i had warranty then I would not be reaching out to them for assistance in replacing the transmission.

NHTSA complaint #11649578 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Port Barre, LA

VEHICLE SPEED CONTROL

While driving on the interstate and coming over an overpass there was unavoidable debris located in the road. Immediately after passing over the debris there was a loud noise followed by jerking and the RPM's revved up almost like the car was in neutral. I let up off of the accelerator and then tried to accelerate again. The car would not go faster than 30mph and will not shift out of 3rd gear. I had the car towed to the dealership and the diagnostic codes reflected vehicle speed sensor and there was no physical damage that was visible under the car. I was told that the problem was in the transmission and that it would need to be changed and given an estimate that totaled over $10,000. I was also told by the service advisor that this is a known issue with the Infiniti Q50. After doing researching this a common problem and the consumer is having to pay out of pocket if the warranty has ended. This incident could have ended badly while doing 70mph on the interstate and the car just quits moving. With all of the complaints that I have read over in regards to the transmission issues yet no action has been taken to investigate this problem. It is obliviously a manufacturing issue and the consumer should not have to pay out of pocket for defective transmissions. This luxury car was not a cheap purchase. Very disappointed that with so many cases an investigation has never been done. Infiniti should be held accountable and a recall should be issued for this problem. I will not stop until I can get through to someone that can help.

NHTSA complaint #11649291 — an unverified report by a vehicle owner.

2019 Infiniti Q50 Paso Robles, CA

VEHICLE SPEED CONTROL

Vehicle is tramaling or wandering at 50+ mph speeds. Making it dangerously difficult to keep between the lines without constant steering corrections. I have had car aligned and changed the tires. Still issue persists. There are several post online about this issue with the infiniti Q60 and Q50 models.

NHTSA complaint #11636939 — an unverified report by a vehicle owner.

2014 Infiniti Q50 Orlando, FL

VEHICLE SPEED CONTROL

The transmission Valve Assembly Control Module and Vehicle Speed Sensors have both failed. The car will not shift out of 2nd gear and cannot go faster than 40 mph. This is a safety issue. I had my car inspected by a certified mechanic and he diagnosed the problem. He also stated that that he has seen this a lot with Infinitis. I have maintained my car well but this is Not a maintenance issue. There are thousands of infiniti owners online stating that they had the exact same problem. I filed a case with Infiniti #52260861. This is a design flaw with All Infiniti cars and SUV's and it should be a Recall or at a minimum fixed for free by Infiniti. It cost me $3,500 to have my car fixed and this should be paid by Infiniti to me and all other Infiniti owners with this same problem.

NHTSA complaint #11614127 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Anniston, AL

VEHICLE SPEED CONTROL

P0500 vehicle speed sen/cir P0720 a/t veh speed sen/ circuit-or- output speed sensor P1574 ascd vhcl apps sensor - or lcc vhl spd sen (icc models) My safety was put at risk when the vehicle hesitated and stop changing gears while traffic was behind me. The vehicle was inspected by a local dealership which was Nissan and also Infiniti including a transmission shop named ammco. There were no warning lights that would indicate the vehicle was failing until April the 5th

NHTSA complaint #11613558 — an unverified report by a vehicle owner.

2014 Infiniti Q50 Charlotte, NC

VEHICLE SPEED CONTROL

Valve body failure

NHTSA complaint #11607663 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Carroll, KY

VEHICLE SPEED CONTROL

The valve body went bad at 164k miles. Im not the only one. On all the forums and fb groups im on, there are hundreds of valv bodys going bad on the q50s for this general area of the year. On my facebook group i have seen 4 people in the past 2 days with theirs going out. Code p0720. Mine is being hauled to the shop right now so i dont have paperwork of replacement at this time for a few days

NHTSA complaint #11606710 — an unverified report by a vehicle owner.

2014 Infiniti Q50 Riverside, NJ Crash

VEHICLE SPEED CONTROL

Traction Control did not function when needed. I had my breaks and rotors replaced two days prior to the accident, which may have had an impact on the performance of the vehicle. Insurance representatives did look over the vehicle, as it is now in their possession. However, I do not feel as though they took the time to look into my concerns. There was no warnings on the Dash.

NHTSA complaint #11566220 — an unverified report by a vehicle owner.

2015 Infiniti Q50 Fayetteville, GA

VEHICLE SPEED CONTROL

My car would not accelerate over 40 mph randomly after work. Once i noticed and tried to shift to a lower gear the car did not shift gears at all. When these things first happened there was no indicator lights on. The next morning the check engine light came on and the code pulled was P0720. After finding a repair shop to look further into the issue I was advised the car needed a new transmission to fix the issue. $4,000+ for the repair and as i google the issue I see that this is a common issue and it seems to always happen unexpectedly side note: also should be a recall on driver side blend door.. i almost died this summer due to cold air only blowing on one side in the middle of summer in 100• degree weather.

NHTSA complaint #11548342 — an unverified report by a vehicle owner.

Other Infiniti Q50 problems