Gaz 29 B1805 Engine Trouble Code
What is Gaz 29 B1805?
Gaz 29 B1805 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.
B1805 on the Gaz 29
In cold climates, Gaz 29 vehicles frequently log B1805 during the first winter of ownership. Condensation inside the throttle body creates a temporary short circuit in the position sensor wiring, which clears once the engine warms up — but the fault code remains stored.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Vehicle: | Gaz 29 |
| Brand: | Gaz |
| Model: | 29 |
| Code: | B1805 |
B1805 Gaz 29 Symptoms
Check Engine Light
Illuminated Gaz 29 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Gaz 29
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Gaz 29
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 29 B1805
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:
Brake switch circuit concerns may involve open or shorted BPP circuits, damaged switches, or misadjustment. Verify stoplight function and follow proper self-test procedures per service manual.
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 29 B1805 Repair Cost
Fuel injector cleaning service on the Gaz 29 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.
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 29
A catalytic converter is often condemned on the Gaz 29 when B1805 appears and an efficiency code is present. Before replacement, verify that the upstream oxygen sensor is not slow-responding — a lazy O2 sensor mimics catalytic inefficiency perfectly.
DIY Repair Guide: B1805 on Gaz 29
Replacing the spark plugs on the Gaz 29 is rated a difficulty 2/5 for home mechanics. The top-mounted plug access on this engine requires a 3/8" extension and a 14mm spark plug socket. Always torque to the manufacturer's specification to avoid cracking the cylinder head.
Preventing B1805 on the Gaz 29
For Gaz 29 owners in high-humidity climates, applying electrical contact cleaner and dielectric grease to the ECU connector pins every two years prevents the corrosion-related signal errors that register as B1805.
Frequently Asked Questions — Gaz 29 B1805
A: Almost certainly yes. Most faults that trigger B1805 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.