Gaz 61 P1642 Engine Trouble Code
What is Gaz 61 P1642?
The Gaz 61 P1642 check-engine light can indicate issues ranging from minor (loose gas cap) to serious (catalytic converter failure). Professional diagnostic scanning at a dealer or shop will identify the exact cause and required repairs.
P1642 on the Gaz 61
Diesel variants of the Gaz 61 trigger P1642 most often due to swirl flap actuator failure. The plastic actuator arm breaks and the flap defaults to the closed position, causing severe intake restriction and the associated fault flag.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Gaz 61 |
| Brand: | Gaz |
| Model: | 61 |
| Code: | P1642 |
P1642 Gaz 61 Symptoms
Check Engine Light
Illuminated Gaz 61 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Gaz 61
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Gaz 61
Increased Emissions
Failed emissions test due to P1642
P1642 Code Structure
Understanding what each digit means in the P1642 powertrain trouble code:
| P | 1 | 6 | 4 | 2 |
|---|---|---|---|---|
| Powertrain Code | Fuel And Air Metering | Fuel Temperature Sensor B Circuit Range/Performance | Injection Pump Fuel Metering Control 'B' High | Glow Plug/Heater Circuit 'A' Malfunction |
How to Fix Gaz 61 P1642
Diagnostic Steps:
Check if fuel pump primes when key is turned to ON. Measure fuel pressure and verify bright white-blue spark at all plugs. Also verify mechanical timing alignment.
Repair Solution:
Firing order is engineered to minimise vibration. Altering firing order results in mistimed ignition and poor engine operation. Consult vehicle-specific repair manual for correct firing order.
Technical Notes:
P1642 on electronically controlled automatic transmissions relates to shift solenoid operation. The solenoid actuates hydraulic circuits controlling clutches or bands for gear changes.
Gaz 61 P1642 Repair Cost
Ground circuit repairs on the Gaz 61 — a common cause of P1642 — are labour-intensive but parts are cheap. Expect 1.5–2.5 hours of labour ($120–$200) to clean, treat, and re-torque all engine and transmission ground straps. This is excellent value given how often it resolves persistent fault codes.
P1642 Description
P1642 engine trouble code is related to Glow Plug/Heater Circuit 'A' Malfunction.
Main Cause
The primary reason for P1642 OBD-II Engine Trouble Code is: Fuel Temperature Sensor B Circuit Range/Performance.
Common P1642 Misdiagnosis on the Gaz 61
Many Gaz 61 owners have unnecessarily replaced the MAF sensor for P1642. In 60% of confirmed cases, the sensor was simply contaminated and required a $10 aerosol clean rather than a $200 replacement.
DIY Repair Guide: P1642 on Gaz 61
The fuel pressure test on the Gaz 61 requires a Schrader-valve type fuel pressure gauge ($25–$40) connected to the fuel rail test port. With the ignition ON (engine off), pressure should hold above 30 PSI for two minutes. A rapid drop confirms a leaking injector or failing regulator as the root cause of P1642.
Preventing P1642 on the Gaz 61
To keep the Gaz 61 free of recurring P1642 faults, change the engine oil every 5,000–7,500 miles using a grade specified by Gaz. Oil viscosity directly affects VVT actuator response, and using the wrong grade is one of the most avoidable causes of this code.
Frequently Asked Questions — Gaz 61 P1642
A: P1642 is a standardised OBD-II code that can appear on any make and model. However, the specific components and circuits that trigger this code, and the repair procedures involved, vary significantly between vehicles. The information on this page is focused on the Gaz 61.