Hyundai Eon P1642 Engine Trouble Code
What is Hyundai Eon P1642?
When Hyundai Eon P1642 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.
P1642 on the Hyundai Eon
On the Hyundai Eon, a secondary air injection pump that has seized due to moisture ingress is a common trigger for P1642. The fault is usually only present on cold starts and clears itself after two to three warm-up cycles, making it easy to overlook.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Hyundai Eon |
| Brand: | Hyundai |
| Model: | Eon |
| Code: | P1642 |
P1642 Hyundai Eon Symptoms
Check Engine Light
Illuminated Hyundai Eon dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Hyundai Eon
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Hyundai Eon
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 Hyundai Eon P1642
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:
Power steering pressure switch monitors system operation. If pressure changes are not detected after calibrated speed transitions, this DTC sets. Verify PSP switch operation and check for circuit opens or shorts.
Technical Notes:
P1642 DTCs can be triggered by upstream issues. For example, a dirty MAF sensor may cause incorrect fuel-trim adjustments, leading oxygen sensors to report mixture problems. Address root causes first.
Hyundai Eon P1642 Repair Cost
For Hyundai Eon owners, budget the following for a P1642 repair: EGR valve cleaning $80–$120 or replacement $250–$450, intake manifold gasket $120–$200, and a post-repair reset and road test. Total: $350–$650 at an independent garage.
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 Hyundai Eon
When Hyundai Eon presents P1642 with a concurrent coolant temperature DTC, technicians sometimes replace the thermostat rather than the coolant temperature sensor (CTS). The CTS is a $15–$25 component; the thermostat job carries 1–2 hours of additional labour.
DIY Repair Guide: P1642 on Hyundai Eon
The throttle body on the Hyundai Eon can be cleaned without full removal. Use a clean rag and throttle body cleaner spray with the engine off and cool. After cleaning, an idle relearn is mandatory: disconnect the battery for 10 minutes, reconnect, and allow the engine to idle for 10 minutes undisturbed.
Preventing P1642 on the Hyundai Eon
Inspecting the Hyundai Eon wiring harness conduit grommets annually — especially the floor pan grommet — costs nothing and takes 10 minutes. Catching moisture ingress early eliminates the most common electrical trigger for P1642 on this model.
Frequently Asked Questions — Hyundai Eon P1642
A: It depends on the severity. If the check-engine light is steady, it is generally safe to drive to a workshop within the next few days. If the light is flashing, pull over safely as soon as possible — a flashing light indicates an active misfire that can cause expensive catalytic converter damage within minutes.