Fuel Pump Secondary Circuit Intermittent
The P0233 code indicates an intermittent fault in the fuel pump secondary circuit, which includes the wiring, connectors, and relay that supply power to the fuel pump. This can cause the fuel pump to operate erratically, leading to inconsistent fuel pressure and potential drivability issues. The problem is often due to loose or corroded connections, damaged wiring, or a failing fuel pump relay.
01. Most Common Causes
- Loose or corroded electrical connections in the fuel pump circuit
- Damaged wiring or short circuit in the fuel pump harness
- Faulty fuel pump relay
- Intermittent fuel pump motor failure
02. Symptoms You Will Notice
- Intermittent engine stalling or hesitation
- Difficulty starting the engine
- Check Engine Light illuminated
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data to capture conditions when the fault occurred.
Step 2: Visually inspect the fuel pump relay, fuse, and wiring harness for damage, corrosion, or loose connections.
Step 3: Test the fuel pump relay and circuit continuity using a multimeter.
Step 4: Monitor fuel pressure with a gauge while wiggling the wiring harness to reproduce the intermittent fault.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended as the intermittent fuel pump operation can cause sudden stalling, which is dangerous, especially at high speeds.
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 fuel pump itself needs replacement.