DTC P0456 CAUSED BY EVAP LEAK AT VENT CONTROL VALVE O-RING This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
full bulletin at NHTSA ↗2005 INFINITI QX56 engine problems
moderate 4 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Complaints
4
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 4 engine complaints filed for the 2005 INFINITI QX56, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 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
No new NHTSA engine complaint has been filed on this vehicle in over 11 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
INFINITI; DTC P0456 CAUSED BY EVAP LEAK AT VENT CONTROL VALVE O-RING This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
full bulletin at NHTSA ↗QX56; REVISED UPPER OIL PAN AND TIMING CHAIN CASE PROCEDURES This bulletin is no longer active. Please discard previous versions of ITB10-055.
full bulletin at NHTSA ↗2005-2015 INFINITI VEHICLES; ECM REPROGRAMMING SERVICE INFORMATION This bulletin is no longer active. Please discard previous versions of ITB15-024.
full bulletin at NHTSA ↗VK56 CONNECTING ROD CAP BOLT SERVICE INFORMATION SERVICE INFORMATION A change has been made to the connecting rod cap bolt service part. The new service part (B in Figure 1) is visually different, but is a direct replacement for the original equipment part. IMPORTANT: See page 2 for the procedure to inspect the cap bolt service part for excessive stretch. If replacement of a single connecting rod cap bolt is indicated for any given connecting rod, both connecting rod cap bolts of the affected connecting rod must be replaced as a set.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 1 most recent
This letter is in reference to a previous complaint filed with Infiniti consumer affairs on december 3, 2009, regarding my vehicle shutting completely down, stalled out, not moving in the drive or reverse position at a busy intersection on a rainy stormy evening. This occurrence could have caused a serious accident or worse, a fatality. As a result of police assistance and having my vehicle towed…
Had engine trouble with your 2005 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 2005 INFINITI QX56?
It's a documented issue but not catastrophic. 4 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?
Based on the 4 complaints filed, engine issues most often appear around 97,938 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
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/2005/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.