Injector Circuit Malfunction - Cylinder 1
The P0201 code indicates a problem in the electrical circuit of the fuel injector for cylinder 1. This can be caused by a faulty injector, wiring issues, or a problem with the engine control module (ECM). The injector circuit includes the injector itself, the wiring harness, connectors, and the ECM driver. A malfunction can lead to improper fuel delivery, causing misfires and performance issues.
01. Most Common Causes
- Faulty fuel injector (cylinder 1)
- Open or shorted wiring in injector circuit
- Poor electrical connection at injector or ECM
- Failed ECM (rare)
02. Symptoms You Will Notice
- Engine misfire (cylinder 1)
- Rough idle or hesitation
- Check Engine Light on
- Decreased fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect injector connector and wiring for damage.
Step 3: Use a multimeter to test injector resistance (typically 11-18 ohms).
Step 4: Check for power and ground at injector connector with key on.
Step 5: Perform a cylinder balance test or injector pulse test with a noid light.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause misfires, catalytic converter damage, and poor performance. Short trips to a repair shop are okay.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, but can be higher if the injector or ECM needs replacement.