Severity High
P029D

Cylinder 1 Fuel Injector Leak

📅 Last reviewed: July 2026
What does the P029D code mean?

The P029D code indicates that the engine control module (ECM) has detected a fuel leak from the injector in cylinder 1. This can be caused by a stuck-open injector, damaged O-rings, or a cracked injector body, leading to excessive fuel entering the cylinder, which can cause misfires, rough idle, and potential engine damage if not addressed promptly.

High
Severity
$50-$150
Typical Cost
High
Frequency

1. Most Common Causes

2. Symptoms You Will Notice

3. Step-by-Step Diagnosis

1

Step 1: Scan for codes and record freeze frame data.

2

Step 2: Perform a fuel pressure test to check for leaks.

3

Step 3: Visually inspect injector and O-rings for damage.

4

Step 4: Use a noid light or injector test to check electrical signal.

5

Step 5: Perform a cylinder balance test to isolate the faulty injector.

4. Frequently Asked Questions

Is it safe to drive with this code?

No, driving with a leaking injector can cause engine misfires, catalytic converter damage, and potential hydrolock. It is best to have it repaired immediately.

How much does it cost to fix?

The cost typically ranges from $50 to $150 for a single injector replacement, including parts and labor, but may vary depending on vehicle make and model.

5. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

6. Related Codes

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