OBD-II diagnostic trouble code
P0100Caution

Mass or Volume Air Flow Circuit Malfunction

The mass airflow sensor circuit isn't sending a usable signal at all, which leaves the engine computer guessing at how much air is entering the engine and can cause rough running or stalling.

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Code names are compiled from open/standardized SAE and ISO references. Explanations, symptoms, causes and fixes are original. Covers generic (P0/C0/B0/U0) codes only — manufacturer-specific codes are planned for a future update.

Frequently asked questions

Can I drive with P0100?

You can usually keep driving with P0100, but don't put it off — the underlying cause can get worse or lead to further damage the longer it goes unaddressed. Get it diagnosed as soon as you reasonably can.

How much does it cost to fix P0100?

The cost varies too much by cause and vehicle to give a single figure here — a diagnosis will narrow it down.

What causes P0100?

AS
Reviewed by Artyom SemenovAutomotive Editor · Fact-checked by Yauheni Kapliarchuk, Editor-in-Chief
Code names compiled from open SAE/ISO references; explanations and repair guidance are original editorial content
Last verified: 09 Jul 2026 · Our methodology