Gaz 31 B1805 Engine Trouble Code
What is Gaz 31 B1805?
When Gaz 31 B1805 code appears, first check your gas cap. Pull over safely, ensure it is tight, and inspect for cracks. A loose or damaged gas cap affects fuel-system pressure and emissions. A replacement cap costs about $3–$10. This simple fix can resolve the code and improve fuel economy.
B1805 on the Gaz 31
The Gaz 31 uses a dual-port fuel injection architecture that is sensitive to ethanol content variations. When E10 fuel is substituted with E5, or vice versa, the fuel trim corrections can cross the DTC threshold and store B1805 in the ECU.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Vehicle: | Gaz 31 |
| Brand: | Gaz |
| Model: | 31 |
| Code: | B1805 |
B1805 Gaz 31 Symptoms
Check Engine Light
Illuminated Gaz 31 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Gaz 31
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Gaz 31
Increased Emissions
Failed emissions test due to B1805
B1805 Code Structure
Understanding what each digit means in the B1805 body trouble code:
| B | 1 | 8 | 0 | 5 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering | Engine Oil Temperature Sensor Malfunction | Cold Start Injector 1 Malfunction | Crankshaft Position Sensor B Circuit Malfunction |
How to Fix Gaz 31 B1805
Diagnostic Steps:
Oxygen sensors measure exhaust gas oxygen content to optimise air-fuel ratio. This optimisation improves fuel economy and reduces emissions. Sensors degrade over time and require periodic replacement.
Repair Solution:
VSS concerns may stem from noisy input signals caused by RFI/EMI from ignition wires, charging circuits, or aftermarket equipment. Verify VSS reads 0 mph when transmission is in Park.
Technical Notes:
B1805 DTC specifically relates to camshaft timing. When cam timing is over-retarded, the check-engine light illuminates and this code sets. Verify VCT solenoid operation and check for contamination.
Gaz 31 B1805 Repair Cost
A Gaz 31 B1805 fault caused by ignition coil failure costs roughly $90–$160 per coil including labour. Replacing all coils simultaneously — rather than one at a time — is recommended because coils typically age at similar rates. This preventive approach keeps total cost below $500.
B1805 Description
B1805 engine trouble code is related to Crankshaft Position Sensor B Circuit Malfunction.
Main Cause
The primary reason for B1805 OBD-II Engine Trouble Code is: Engine Oil Temperature Sensor Malfunction.
Common B1805 Misdiagnosis on the Gaz 31
The Gaz 31 is frequently taken to workshops for a B1805 fault where the technician replaces the throttle position sensor (TPS). In a significant proportion of cases, the root cause is a loose or cracked vacuum hose downstream of the throttle body that should have been found in a basic visual inspection.
DIY Repair Guide: B1805 on Gaz 31
When attempting DIY diagnosis of B1805 on your Gaz 31, a smoke machine test is the gold standard for finding vacuum leaks. Rental tools are available from most auto parts stores for $0–$20/day, or you can fabricate a makeshift tester using a hand vacuum pump and soapy water spray.
Preventing B1805 on the Gaz 31
For diesel Gaz 31 owners, a DPF (Diesel Particulate Filter) regeneration run on the motorway every 500 miles prevents soot blockage that back-pressures the exhaust and forces B1805 flags via the pressure differential sensors.
Frequently Asked Questions — Gaz 31 B1805
A: If your Gaz 31 is within the factory powertrain warranty period (typically 3–5 years or 60,000–100,000 miles depending on region and generation), B1805 repairs caused by component defects should be covered. Bring your service history to the dealer appointment.