Gmc Canyon P1642 Engine Trouble Code
What is Gmc Canyon P1642?
The Gmc Canyon 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 Gmc Canyon
Diesel variants of the Gmc Canyon 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: | Gmc Canyon |
| Brand: | Gmc |
| Model: | Canyon |
| Code: | P1642 |
P1642 Gmc Canyon Symptoms
Check Engine Light
Illuminated Gmc Canyon dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Gmc Canyon
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Gmc Canyon
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 Gmc Canyon 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.
Gmc Canyon P1642 Repair Cost
Ground circuit repairs on the Gmc Canyon — 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 Gmc Canyon
On Gmc Canyon vehicles, the turbo boost solenoid and the MAP sensor feed into the same diagnostic path. P1642 caused by a faulty boost solenoid is sometimes charged to the customer as a MAP sensor replacement, doubling unnecessary parts spend.
DIY Repair Guide: P1642 on Gmc Canyon
Battery terminal cleaning on the Gmc Canyon is a 5-minute job that resolves a surprising number of P1642 intermittents. Use a wire brush and a bicarbonate of soda solution to clean corrosion, then apply a thin coat of petroleum jelly to the terminals after refitting.
Preventing P1642 on the Gmc Canyon
The Gmc Canyon coolant temperature sensor plays a role in fuel enrichment during warm-up. Replacing it as a precaution at 80,000 miles ($25–$40 DIY) prevents the faulty cold-start enrichment that can lead to P1642.
Frequently Asked Questions — Gmc Canyon 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 Gmc Canyon.