Infiniti I30 B1566 Engine Trouble Code
What is Infiniti I30 B1566?
Infiniti I30 B1566 indicates potential catalytic converter failure. If completely failed, your vehicle may not run properly and fuel economy will suffer significantly. Average replacement cost is $2,000–$2,140. This repair requires professional service and should not be delayed.
B1566 on the Infiniti I30
For Infiniti I30 owners, diagnosing B1566 correctly requires ruling out a faulty camshaft position sensor before replacing more expensive components. The sensor wiring harness on this model runs close to the exhaust manifold and is prone to heat-related insulation damage.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Vehicle: | Infiniti I30 |
| Brand: | Infiniti |
| Model: | I30 |
| Code: | B1566 |
B1566 Infiniti I30 Symptoms
Check Engine Light
Illuminated Infiniti I30 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Infiniti I30
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Infiniti I30
Increased Emissions
Failed emissions test due to B1566
B1566 Code Structure
Understanding what each digit means in the B1566 body trouble code:
| B | 1 | 5 | 6 | 6 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering | Fuel Composition Sensor Circuit Malfunction | Cylinder 4 Contribution/Balance Fault | Ignition Coil A Primary/Secondary Circuit Malfunction |
How to Fix Infiniti I30 B1566
Diagnostic Steps:
The catalytic converter has oxygen sensors before and after it. When warm and in closed-loop mode, the upstream O2 sensor reading should fluctuate, while downstream should remain steady.
Repair Solution:
Disconnected, dirty, or fouled spark plugs commonly prevent proper engine operation. Replace spark plugs every season or 25 hours. Verify proper spark plug gap. If plugs are good, check ignition components: spark plug wires, coils, and ignition module.
Technical Notes:
Parts or components should not be replaced based solely on B1566 DTC. Consult your vehicle service manual for proper diagnostic procedures, possible causes, and required testing before replacement.
Infiniti I30 B1566 Repair Cost
A complete diagnostic health-check on the Infiniti I30 before committing to any single repair costs $120–$180 at a dealership with live-data capability. This investment pays for itself if it prevents unnecessary part replacement, which is the single most common mistake when diagnosing B1566.
B1566 Description
B1566 engine trouble code is related to Ignition Coil A Primary/Secondary Circuit Malfunction.
Main Cause
The primary reason for B1566 OBD-II Engine Trouble Code is: Fuel Composition Sensor Circuit Malfunction.
Common B1566 Misdiagnosis on the Infiniti I30
The Infiniti I30 purge valve for the EVAP system is located in an area prone to heat damage. It is often overlooked in favour of replacing the carbon canister ($120–$200) when the valve itself ($25–$50) is the failed component for B1566.
DIY Repair Guide: B1566 on Infiniti I30
For Infiniti I30 owners without a scan tool, a free diagnostic check is available at most franchised Infiniti dealers during a courtesy health-check appointment. This provides the DTC number needed to research the exact cause of B1566 before committing to any repair.
Preventing B1566 on the Infiniti I30
On the Infiniti I30, using a quality fuel system cleaner (added to the fuel tank every 10,000 miles) helps prevent injector deposit build-up that indirectly triggers B1566 through fuel-trim imbalances.
Frequently Asked Questions — Infiniti I30 B1566
A: If your Infiniti I30 is within the factory powertrain warranty period (typically 3–5 years or 60,000–100,000 miles depending on region and generation), B1566 repairs caused by component defects should be covered. Bring your service history to the dealer appointment.