Subaru 1400 P1582 Engine Trouble Code
What is Subaru 1400 P1582?
With Subaru 1400 P1582, you may drive for several weeks with a malfunctioning MAF sensor, but expect decreased fuel economy and eventual stalling. Shop replacement costs $240–$400 depending on vehicle. The labour is straightforward, with most cost from the part itself.
P1582 on the Subaru 1400
Independent workshop data shows that Subaru 1400 vehicles with P1582 resolve approximately 40% of cases after a throttle body cleaning and idle relearn procedure. This is always the recommended first step before investing in new sensors.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Subaru 1400 |
| Brand: | Subaru |
| Model: | 1400 |
| Code: | P1582 |
P1582 Subaru 1400 Symptoms
Check Engine Light
Illuminated Subaru 1400 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Subaru 1400
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Subaru 1400
Increased Emissions
Failed emissions test due to P1582
P1582 Code Structure
Understanding what each digit means in the P1582 powertrain trouble code:
| P | 1 | 5 | 8 | 2 |
|---|---|---|---|---|
| Powertrain Code | Fuel And Air Metering | Fuel Composition Sensor Circuit Malfunction | Ignition/Distributor Engine Speed Input Circuit Malfunction | Glow Plug/Heater Circuit 'A' Malfunction |
How to Fix Subaru 1400 P1582
Diagnostic Steps:
Poor running symptoms align with MAP sensor malfunction. In some cases, a faulty MAP sensor will not trigger a code. The issue may represent separate wiring concerns requiring individual diagnosis.
Repair Solution:
Most manufacturers number cylinders sequentially from front to back. Ford V-engines start with cylinder 1 at front left. In V-6 engines, cylinder 4 is front right; in V-8 engines, cylinder 5 occupies that position.
Technical Notes:
For P1582, verify VCT solenoid operation. Look for stuck or sticking valves caused by contamination. Consult vehicle-specific repair manual for proper component testing procedures.
Subaru 1400 P1582 Repair Cost
Fuel injector cleaning service on the Subaru 1400 costs $150–$300 for an ultrasonic bench-clean of all injectors with flow-test certification. On-car induction cleaning is a cheaper ($80–$120) first step but is less thorough for heavily fouled injectors.
P1582 Description
P1582 engine trouble code is related to Glow Plug/Heater Circuit 'A' Malfunction.
Main Cause
The primary reason for P1582 OBD-II Engine Trouble Code is: Fuel Composition Sensor Circuit Malfunction.
Common P1582 Misdiagnosis on the Subaru 1400
Workshop technicians sometimes replace the entire ignition coil assembly on the Subaru 1400 when P1582 accompanies a cylinder-specific misfire. In many cases, only the spark plug in the misfiring cylinder has fouled; a $8 plug replaces a $140 coil pack.
DIY Repair Guide: P1582 on Subaru 1400
The coolant temperature sensor on the Subaru 1400 is a straightforward DIY item (difficulty 2/5). Have a drain tray ready for the small amount of coolant that spills when the sensor is removed. Top up the cooling system afterwards and check for air pockets.
Preventing P1582 on the Subaru 1400
For turbocharged Subaru 1400 models, allowing the engine to idle for 60–90 seconds before shutdown after hard driving reduces turbocharger heat soak and prevents the coking of oil that blocks VVT galleries — a known secondary trigger of P1582.
Frequently Asked Questions — Subaru 1400 P1582
A: Almost certainly yes. Most faults that trigger P1582 cause the ECU to operate in open-loop mode or apply overly rich fuel trims, both of which increase fuel consumption by 5–15%. Resolving the fault promptly pays for itself in fuel savings over time.