Power Train Problems of Infiniti Q50 - part 1

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.

See all problems of the 2015 Infiniti Q50 🔎.

Shortly after purchasing the vehicle, I began experiencing serious performance issues. While driving, the vehicle suddenly lost power, would not accelerate properly, and warning lights appeared on the dashboard. The vehicle eventually shut off while in operation. The vehicle was inspected by a dealership, which initially stated there were no issues. However, the problem continued and worsened. The vehicle was then inspected by an authorized Infiniti dealership, where technicians identified a consistent knocking noise coming from the engine. The dealership indicated that the noise is consistent with internal engine damage and recommended further inspection and likely engine replacement. The issue developed very shortly after purchase, and there were no prior indications that the vehicle had been damaged or misused. The sudden loss of power and engine failure created a potential safety hazard, especially while driving in traffic, as the vehicle was unable to accelerate and could have led to a dangerous situation. The vehicle is currently available for inspection, and the issue has been confirmed by a certified dealership. The cause of the failure is currently under further evaluation.

See all problems of the 2019 Infiniti Q50 🔎.

Transmission control body. Lost of speed during driving which put me in danger of being hit from behind on the highway. The car was scanned and came up the code p0500 and p0720.

Ever since I got the vehicle transmission is trying to give out on the vehicle takes too long to shift gears, takes more rpm to shift gears.

See all problems of the 2020 Infiniti Q50 🔎.

Driveshaft broke while driving down the road!!.

See all problems of the 2014 Infiniti Q50 🔎.

Filing this complaint regarding a safety-related defect involving the turbocharger system on my 2018 Infiniti Q50. The vehicle has approximately 46,000 miles and is 8 years old. Infiniti/Nissan has acknowledged through its own technical service bulletins (tsbs) that turbocharger failure on 2016–2018 Q50 3. 0t vehicles is a known defect. Nissan’s documentation identifies issues such as turbo oil seal leaks, reduced engine power, smoke, and potential catastrophic engine failure, and provides an extended warranty of up to 10 years or 120,000 miles due to the safety risks associated with sudden power loss. My vehicle experienced turbocharger failure consistent with these known defects, resulting in loss of engine power, which presents a serious safety hazard, particularly during highway driving, merging, or intersections. Sudden loss of propulsion increases crash risk and endangers vehicle occupants and others on the road. In some cases, turbo failure can occur with little or no warning, further increasing risk. The failure was confirmed by Infiniti/Nissan service departments, and the vehicle remains available for inspection. Carmax insurance approved the engine repair, acknowledging mechanical failure; however, they declined to approve turbocharger repair specifically because Infiniti has issued a known TSB and extended warranty covering turbo failure, deferring responsibility to the manufacturer. Despite the vehicle being within the extended warranty limits, Nissan denied coverage, claiming the vehicle has a “branded title. ” this claim is unsupported by VIN reports, the loan originator, and carmax’s own title search prior to leasing all confirm the title is not branded. Nissan has provided no documentation supporting its assertion. Nissan n. A. Reviewed and closed the matter despite the known safety defect and lack of evidence for the title claim. Represents a safety-related defect and improper denial of a manufacturer-recognized safety remedy, warranting NHTSA review.

See all problems of the 2018 Infiniti Q50 🔎.

I am the owner of a 2017 Infiniti Q50 purchased in 2019. My vehicle has suffered three separate turbocharger failures in four years: 2021 (~75,000 miles): turbocharger failure; replaced under my extended warranty (~$6,000 authorization). 2023 (~98,000 miles): turbocharger failure; replaced again under extended warranty (~$6,000 authorization). 2025 (143,000 miles): diagnostic confirms another turbocharger failure; quoted $8,900 out of pocket because my extended warranty has expired. These failures follow the classic symptoms of excessive exhaust smoke and mil illumination that Infiniti has explicitly linked to premature turbocharger bearing wear in the February 2025 “limited emission warranty extension” for 2016–2018 Q50 and 2017–2018 q60 vehicles. Infiniti’s bulletin states the company “is conducting a warranty extension to full useful life (ful) of 10 years or 120,000 miles” for select turbo assemblies where white smoke/oil-leak with mil-on requires turbo replacement, and explains the reason as “possibility that the turbocharger bearing may leak engine oil internally due to premature wear. ” Infiniti’s public owner-facing campaign page likewise describes this extension and its terms (10 years/120,000 miles), including reimbursement for qualifying prior repairs. Infiniti assist while my current mileage exceeds 120,000 miles, my car has required two full turbo replacements before 100,000 miles and now requires a third at 143,000 miles. This pattern evidences a latent defect present well within the extension period and is consistent with the failure mode Infiniti acknowledges. They have offered no help and only assume 50% responsibility when they 100% have manufactured defective and poorly labored parts.

See all problems of the 2017 Infiniti Q50 🔎.

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.

I received a check engine light will driving which is now indicated as code p0720 and p0500. The car refused to shift past 3rd gear and began to sputter and would not allow me to go past 25mph disrupting the flow of traffic.

The contact owns a 2015 Infiniti Q50. The contact stated while driving 40 mph, the accelerator was depressed; however, the vehicle failed to shift into gear properly, with the check engine warning light illuminated. The vehicle was able to be restarted. The vehicle was taken to an independent mechanic, where it was diagnosed that the transmission valve body had failed, and the transmission needed to be replaced. The vehicle was not repaired. The dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 94,150.

Transmission intermittently will not shift to the next gear. Sometimes will not shift from first gear, other times will not shift from 3rd gear. Sometimes no issue at all. It is intermittent and no warning to when the issue might happened. It happens when trying to accelerate and has put me in an unsafe situation trying to accelerate on the highway or around town.

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.

Air bag light suddenly said “passenger airbag off”. Don’t have to brake to switch gears. Steering at times feels a bit off.

Front and middle crossmember rusted out to the point they have no more structural effects issues discovered while fixing a know issue to these models : rusted out and leaking engine and transmission oils pans I had confirmation from the dealership and other independent repair shop that leaking oils pans are common for those models and can cause engine and transmission failure. For the crossmembers they are important structural components that directly affect suspension/direction and drivetrain secureness. If the plastic shrouds/cover are not taken off during inspection those issues will goes undetected until one of them reaches failure.

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.

Transmission failure without warning!!.

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.

Car has white smoke coming from the exhaust and the oil level keeps decreasing. Car stalls and takes time to accelerate p0106 code pops up from engine. There’s a rattle and whine noise coming from the engine bay. Also the gas was stuck accelerating. Had to switch the car to neutral so it does continue accelerating. After switching to neutral I was able to decrease power to the wheels and had to pull over on the road.

Vehicle was parked in my driveway with the engine running for about 5-10 minutes while I was going into the house to turn off my alarm, then return to take out 2 of my elderly dogs; & finally to take out my other dogs. I then returned to the car, opened the driver's side front door & reached in to push the "stop" button on the dash. As soon as I did, the vehicle immediately went into reverse & pulled me down the driveway by the open door. The vehicle continued down the driveway & crossed the street, hitting a fire hydrant in my neighbor's yard across the street. I never physically got into the vehicle to do the steps required to put the vehicle into reverse, I. E. Putting my foot on the brake & depressing the transmission shift button. I contacted the dealership where I purchased the vehicle after the incident & explained what had happened. I spoke to francisco, but he said there was nothing he could do unless I wanted to pay for diagnostics on the vehicle. I explained that the vehicle had clearly malfunctioned since I was not physically inside of the vehicle to put it into reverse. I asked him to document the incident, but he said he was unable to & suggested I contact Infiniti consumer affairs. I did that immediately after speaking with francisco, & gave a detailed description of the incident. I was given a case number at that time. I called another Infiniti dealership to explain the situation to ask about diagnostics, & was informed that the car's computer would not give an error code for the car going into reverse. I called to speak to my dealership service advisor & was able to schedule a diagnostics appointment at no charge. I did an internet search & discovered it could be a linkage issue, which is a safety issue & the recommendation was for the vehicle to not be driven. I have since scheduled an inspection with Nissan corp. But the rep was not receptive to my request for repairs. I supplied a video to the dealership, but Nissan said they did not have it.

See all problems of the 2023 Infiniti Q50 🔎.

The contact owns a 2017 Infiniti Q50. The contact stated while driving 40 mph and attempting to accelerate, the rpm increased quickly; however, the vehicle lost motive power, prompting the contact to discontinue driving the vehicle. Upon arriving at the residence, the contact shifted the vehicle into park and released the brake pedal, and the vehicle started rolling forward. The contact engaged the parking brake to secure the vehicle. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA campaign number: 24v470000 (power train); but the VIN was not included. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA hotline for assistance. The failure mileage was 112,000.

The car has only 50,000 miles and the valve body of the car just burnt out. I’ve done all the mandatory/ recommended maintenance and with the history of the brand I expected better quality of their product. Would greatly appreciate the accountability on this issue and some effort to fix this for the population.

See all problems of the 2016 Infiniti Q50 🔎.

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.

I received a recall notice (folded information card) from infinity in the mail in about August 2024 regarding recall NHTSA 24v-470-r24a7. I also received an email from infinity on August 28, 2024 with subject "your Q50 is due for important recall repairs " and noted it stated recall code r24a7/r24a5: NHTSA 24v-470: recall description Q50/q70 prop shaft. I contacted infinity to schedule the repair and received a confirmed email service appointment for October 4th 2024. When I arrived at the dealership the service department told me they did not have parts but would change my oil and do other service for a fee. All I wanted was the recall fixed. In total I've been to the dealer 3 times and been always told that they have not received parts from the manufacturer. Today I called infinity consumer affairs department at 1-800-662-6200 and spoke to "dennis". He did little but talk in circles and did nothing to provide information and when the recall would be fixed. Since I was getting no information and he was not listening or helping I told him I was ending the call and calling the NHTSA, which I did and spoke with tyronda. Confirmation number for call she gave me is [xxx] for our call. After my repeated efforts and complaints, infinity appears to have no interest on fixing the vehicle recall they first advised me of in August, only seemingly "going through the motions" as slow as possible. My car is not fixed after about 4 months and they have done nothing to contact me as to when it will be repaired. That is my complaint information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Valve body went out at 90k miles . This is way common and I took care of the car.

Driving car normally and car randomly put itself in 3rd gear and slammed down hard almost making me cause a crash and injury to me. Went to dealership they told me I need a new transmission due to valve body that they don’t sell by itself. This is the second time a replacement was done and it happened.

Valve body failure.

The contact owns a 2016 Infiniti Q50. The contact stated upon attempting to drive from a complete stop, the vehicle failed to respond. The contact stated that upon attempting to drive the vehicle 30 minutes later, the vehicle responded as needed. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, where the vehicle was diagnosed that the valve body had failed. The mechanic determined that the valve body and the entire transmission needed to be replaced. The vehicle was not repaired. An unknown dealer was notified of the failure and charged a fee for the repair. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 77,636. The VIN was not available.

I was driving down the highway and my car started to shut down and started to make a knocking sound inside the engine bay, putting at risk other drivers, so I turned on my hazards and pulled to the shoulder of the road,the car wouldn’t turn on so I called a tow truck. Took the car to dealer and stated engine is seized.

Transmission will not shift out of 3rd gear. I was driving down the freeway in 7th gear doing 75mph when all of sudden the transmission threw itself into 2nd gear then to 3rd. It felt like I was driving over a very large boulder and my transmission was being ripped out from under the car. Then my check engine light came on. So I had it towed home. I went for a test drive and the car will shift 1st, 2nd then 3rd but won’t go to 4th. It just stays in 3rd, it doesn’t slow down, it continues to rise in rpm and speed but won’t go out of 3rd gear. It also will not go into the manual shift mode either. I have read online about thousands of others with the same exact transmission having the same exact problem. I almost was not able to control my car so it most definitely is a big safety issue. I had autozone run a scan on it and it popped up all of these codes. My dash had zero warning lights at all before the incident happened.

The contact owns a 2015 Infiniti Q50. The contact stated that while driving at an undisclosed speed, the vehicle stalled. The contact was able to drive the vehicle off the highway and parked the vehicle. The contact stated that the failure occurred while the contact was driving on a busy highway. The vehicle was towed to the dealer where it was diagnosed with transmission valve body failure. The contact was informed that the transmission valve body needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 74,000.

My engine light came on at 115,946 miles causing my vehicle not to accelerate or shift properly which could have resulted in a accident. The vehicle was diagnosed at local Nissan dealership with code p0720 and p0500 stating vehicle need a transmission. Prior to this diagnose this vehicle was diagnose twice by a Nissan and Infiniti dealership concerning the shifting and acceleration issues but could not duplicate the issue at the time. I see where numerous car buyers are stating they’re having the same issues with the Infiniti brand at low miles and high miles.

I was driving on the freeway and suddenly my vehicle would not shift into third geer causing the rpm s to go up to 4-5. As I tried to exit the car started shuddering and I was almost hit by multiple cars. I finally was able to exit and stop to park the vehicle. No warning lights came on at anytime. I had it towed to my mechanic and was told that it was the valve body control. My car only has 86k on it and I have taken exceptional care of it performing all maintenace like clockwork. Was told replacement was 8,500. 00 for entire part including the housing or 4,500 and use my current housing. My mechanic checked with infinity who said they knew of this issue, but there is no recall and the part is only under warranty for 1 year.

Engine overheating and system not keeping engine cool, locks don’t work.

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.

When I was driving in highway, all of a sudden gas paddle stop working no matter how hard I press it is not taking gas paddle and not picking up speed. I was panicking, lucky nobody behind me. Nothing bad happen, but this is very dangerous in my opinion.