Top 10 OBD Codes That Are Usually Safe to Drive With (But Shouldn’t Be Ignored)

If your Check Engine Light is flashing, stop driving immediately.

A flashing light usually indicates active misfire that can damage the catalytic converter.

The list below applies to solid check engine lights only, where the car runs normally.

🔟 OBD Codes That Are Often Safe for Short-Term Driving

1️⃣ P0456 – EVAP Very Small Leak

Usually caused by a loose gas cap.
No drivability issues in most cases.

2️⃣ P0440 – EVAP System Malfunction

Often gas cap, purge valve, or small hose issue.

3️⃣ P0455 – EVAP Large Leak

Still usually safe to drive, but should be fixed.

4️⃣ P0128 – Coolant Temperature Below Thermostat Regulating Temperature

Engine runs too cool.
Typically thermostat-related.
Safe short-term, but reduces fuel economy.

5️⃣ P0133 – O2 Sensor Slow Response

May not affect drivability immediately.

6️⃣ P0171 – System Too Lean (Mild Case)

If no misfires or power loss, short-term driving is possible.
Should be diagnosed soon.

7️⃣ P0172 – System Too Rich (Mild Case)

Can be safe short-term, but may damage catalytic converter over time.

8️⃣ P0500 – Vehicle Speed Sensor

May affect speedometer or ABS.
Engine usually runs fine.

9️⃣ P0442 – Small EVAP Leak

Very similar to P0456.
No performance issues.

🔟 P0101 – MAF Performance (Mild Case)

If the car runs normally and no severe hesitation occurs, it may be safe short-term.

🚫 Codes That Are NOT Safe to Drive With

• P0300 (Flashing light)

• P0335 (Crankshaft sensor – may stall)

• P0087 (Low fuel pressure – may lose power)

• Overheating codes

• Oil pressure codes

These can cause engine damage or unsafe driving conditions.

🔎 How to Know If It’s Safe

It’s usually safe for short-term driving if:

✔ Light is solid
✔ No overheating
✔ No flashing CEL
✔ No loss of power
✔ No stalling

If any of those occur — stop driving.

FAQ

Can I drive with a check engine light on?

Yes, if it’s solid and the car runs normally.

Is a flashing check engine light dangerous?

Yes — stop driving immediately.

How long can I drive with EVAP codes?

Usually safe short-term, but repair soon.

Final Thoughts

Not all OBD codes require immediate towing.

But none should be ignored long-term.

The key is understanding the difference between:

• minor emissions issues

• and engine-damaging faults