P1279 Port Injector Circuit Number 4

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Toyota models with D-4S port injection

What does P1279 mean on a Toyota?

P1279 — Port Injector Circuit Number 4. This Toyota-enhanced code applies to Toyota models with D-4S port injection.

Common causes of P1279

Open number 4 port injector circuit
Failed injector 4
Corroded connector
Harness damage
ECM fault

How to fix P1279

Test injector 4 resistance
Verify pulse signal
Check wiring
Inspect the connector
Replace the injector per findings