Mitsubishi Galant Ix B1566 Engine Trouble Code
What is Mitsubishi Galant Ix B1566?
Mitsubishi Galant Ix 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 Mitsubishi Galant Ix
For Mitsubishi Galant Ix 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: | Mitsubishi Galant Ix |
| Brand: | Mitsubishi |
| Model: | Galant Ix |
| Code: | B1566 |
B1566 Mitsubishi Galant Ix Symptoms
Check Engine Light
Illuminated Mitsubishi Galant Ix dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Mitsubishi Galant Ix
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Mitsubishi Galant Ix
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 Mitsubishi Galant Ix 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.
Mitsubishi Galant Ix B1566 Repair Cost
For Mitsubishi Galant Ix owners, budget the following for a B1566 repair: EGR valve cleaning $80–$120 or replacement $250–$450, intake manifold gasket $120–$200, and a post-repair reset and road test. Total: $350–$650 at an independent garage.
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 Mitsubishi Galant Ix
A common error on the Mitsubishi Galant Ix is attributing B1566 to the crankshaft position sensor when the real fault is a damaged flywheel ring gear. The missing tooth pattern created by ring gear damage is intermittent and generates the same signal anomaly.
DIY Repair Guide: B1566 on Mitsubishi Galant Ix
Replacing the oxygen sensor on the Mitsubishi Galant Ix requires an O2 sensor socket (22mm or 7/8") and penetrating oil applied 24 hours in advance. On vehicles over five years old, the sensor threads often corrode into the bung; heat from a propane torch (briefly applied) is usually sufficient to free them.
Preventing B1566 on the Mitsubishi Galant Ix
The Mitsubishi Galant Ix coolant temperature sensor plays a role in fuel enrichment during warm-up. Replacing it as a precaution at 80,000 miles ($25–$40 DIY) prevents the faulty cold-start enrichment that can lead to B1566.
Frequently Asked Questions — Mitsubishi Galant Ix B1566
A: If your Mitsubishi Galant Ix 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.