Cold Start Injector 1 Malfunction
The cold start injector circuit is malfunctioning, preventing proper fuel delivery during cold engine starts. This code indicates the engine control module detected a fault in the cold start injector system, which enriches the fuel mixture for easier starting in cold temperatures.
What You Might Notice
- Difficult or delayed engine starting in cold weather
- Engine cranks but takes longer to fire up when cold
- No issues starting in warm weather conditions
- Rough idle immediately after cold start
- Check Engine Light illumination
Most Common Causes
- 1
Defective cold start injector
The cold start injector itself has failed electrically or mechanically and cannot spray fuel properly during engine start.
- 2
Faulty engine coolant temperature sensor
The ECT sensor provides incorrect temperature readings to the engine control module, preventing it from activating the cold start injector when needed.
- 3
Open or shorted wiring in cold start injector circuit
Damaged, corroded, or disconnected wiring between the ECM and cold start injector prevents proper electrical signal transmission.
- 4
Faulty intake air temperature sensor
The IAT sensor may provide incorrect readings that affect cold start fuel enrichment logic in the engine control module.
How to Diagnose It
- 1
Check Defective cold start injector — The cold start injector itself has failed electrically or mechanically and cannot spray fuel properly during engine start.
- 2
Check Faulty engine coolant temperature sensor — The ECT sensor provides incorrect temperature readings to the engine control module, preventing it from activating the cold start injector when needed.
- 3
Check Open or shorted wiring in cold start injector circuit — Damaged, corroded, or disconnected wiring between the ECM and cold start injector prevents proper electrical signal transmission.
- 4
Check Faulty intake air temperature sensor — The IAT sensor may provide incorrect readings that affect cold start fuel enrichment logic in the engine control module.
How to Fix It
- 1
Inspect and test cold start injector
Locate the cold start injector, check for visible damage, and test its electrical resistance and fuel spray pattern. Replace if faulty or non-responsive to signal.
- 2
Test engine coolant temperature sensor
Using a multimeter, verify ECT sensor resistance values across the full temperature range. Compare readings to specification and replace if out of range.
- 3
Inspect cold start injector wiring and connectors
Trace the wiring harness from the ECM to the cold start injector, checking for corrosion, loose connections, damaged insulation, or open circuits. Repair or replace damaged sections.
- 4
Test intake air temperature sensor
Verify IAT sensor resistance values match specification at known temperatures. Replace the sensor if readings are inconsistent or out of range.
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