Vehicle dropped speed on the highway and started flashing the service engine soon light. The speed drop was severe and placed me in a dangerous situation on the highway. It also had a whining noise at start when I left . Took it to the dealer, they informed me the timing chain needed to be replaced. The vehicle only had 83k in miles and was just 10k out of warranty. Dealer charged $4000 for…
2012 INFINITI QX56 engine problems
moderate 21 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
21
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 21 engine complaints filed for the 2012 INFINITI QX56, here's the actual mileage breakdown — failures cluster heaviest at 75,000-100,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Engine accounts for 36% of every owner complaint on file for this vehicle — the dominant problem area across 6 categories tracked.
Among the 5 model years of INFINITI QX56 in our records for engine problems, this one ranks #2 by owner-complaint volume.
What owners are reporting 6 most recent
Tl* the contact owns a 2012 Infiniti qx56. The contact stated that the vehicle lost power and failed to accelerate. In addition, there was a humming noise coming from the engine. There were no warning indicators illuminated. The vehicle was taken to west houston Infiniti (12200 katy fwy, houston, tx 77079, (281) 589-8900) where it was diagnosed that the brakes were wearing down. The contact…
At 82,000 miles the check engine light came on indicating both catalytic converters were bad. They are warrantied to 80k miles and of course manufacturer would not help. This needs a recall, google qx56 catalytic converter and see how many people have had this issue.
I own a 2012 QX56. Check engine light comes on and I take it to the dealer. It's the Catalyst System Efficiency Below Threshold (catalytic covers - P0430 code) I was warned before I bought this vehicle about the cats going bad. Infiniti dealer, that I purchased the truck from said "this vehicle has been serviced at an Infiniti dealer since day one. Every possible service that was needed was…
I had my catalytic converter replaced back in december 2016 . There was a recall for catalytic converter so I had it replaced. Now the check engine light is back on so I got it checked out and was told that I needed to replace the catalytic converter again. 35k miles later
I am experiencing the same issues that have been posted by several others on this site with the catalytic converter and the battery (jn8az2ne3c9****, jn8az2nf1c9****, and jn8az2nc9c9****). I took it to get checked out yesterday and just received a call from the technician. He stated that both catalytic converters have to be replaced and it will cost $5,200. If this is a common issue, why is…
Had engine trouble with your 2012 INFINITI QX56?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2012 INFINITI QX56?
It's a documented issue but not catastrophic. 21 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Across the 15 complaints that reported odometer mileage, most engine failures cluster between 82,000 and 130,000 miles, with the median around 96,450. A quarter of owners report trouble before 82,000; a quarter make it past 130,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2012/INFINITI/QX56.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.