Gaz M-21 B1805 Engine Trouble Code
What is Gaz M-21 B1805?
With Gaz M-21 B1805, 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.
B1805 on the Gaz M-21
The turbocharged variants of the Gaz M-21 are more likely to generate B1805 as boost-related over-fuelling trips the ECU threshold. Inspect the intercooler hoses for micro-cracks that allow unmetered air into the intake stream.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Vehicle: | Gaz M-21 |
| Brand: | Gaz |
| Model: | M-21 |
| Code: | B1805 |
B1805 Gaz M-21 Symptoms
Check Engine Light
Illuminated Gaz M-21 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Gaz M-21
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Gaz M-21
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 M-21 B1805
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:
Regular maintenance of indicator and headlight bulbs ensures proper function. Maintain paint condition to prevent rust. Modern products make these maintenance tasks straightforward and accessible.
Technical Notes:
B1805 DTC indicating a sensor fault does not always mean the sensor itself is bad. The issue may stem from the systems being monitored or even the sensor wiring. Proper diagnosis is essential.
Gaz M-21 B1805 Repair Cost
When B1805 appears on a Gaz M-21, a camshaft position sensor swap costs $140–$260 all-in. This is one of the more affordable sensors on this platform. If the wiring harness is also damaged, add $60–$90 for harness repair or section replacement.
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 M-21
Fuel injector replacement is over-prescribed on the Gaz M-21 for B1805 when the actual fault is a weak fuel pump. Low fuel rail pressure causes lean misfire that looks identical to injector failure in static scan data without a live fuel pressure test.
DIY Repair Guide: B1805 on Gaz M-21
For Gaz M-21 owners without a scan tool, a free diagnostic check is available at most franchised Gaz dealers during a courtesy health-check appointment. This provides the DTC number needed to research the exact cause of B1805 before committing to any repair.
Preventing B1805 on the Gaz M-21
The Gaz M-21 heat shield over the exhaust manifold protects the nearby sensor wiring from radiant heat damage. Inspect it for cracks or displacement at every brake service. A $15 replacement shield can prevent $300+ wiring loom repairs.
Frequently Asked Questions — Gaz M-21 B1805
A: Clearing the code without repair allows the fault condition to persist. Depending on the cause, this can lead to catalytic converter damage, increased fuel consumption, and secondary component failures that are significantly more expensive to address than the original fault.