Powertrain Codes

Good

P0104

Mass Air Flow Circuit Intermittent

★★★★ Common diagnostic code

P0104 means the engine or powertrain control module detected a fault related to mass air flow circuit intermittent. The exact repair depends on freeze-frame data, live scan data, visual inspection, and vehicle-specific testing.

Atlas Quality75% · Good
Editorial StatusGood
SeverityMedium
Can I keep driving?Use caution and diagnose before replacing parts.
Typical repair cost$80-$450
Typical labor0.3-1.2 hours

What P0104 Means

P0104 means the engine or powertrain control module detected a fault related to mass air flow circuit intermittent. The exact repair depends on freeze-frame data, live scan data, visual inspection, and vehicle-specific testing.

Before You Replace Anything

Record the evidence first. Clearing codes too early can erase the clues that point to the real fault.

✓ Save freeze-frame data✓ Check for additional trouble codes✓ Look for technical service bulletins✓ Verify battery voltage✓ Verify engine oil level and coolant level✓ Perform a visual inspection✓ Do not clear the codes yet

Common Symptoms

⚠ Check Engine Light⚠ Hesitation⚠ Stalling⚠ Poor acceleration⚠ Rough idle⚠ Poor fuel economy

Most Common Causes

Dirty MAF sensor90%
Air leak after the MAF sensor78%
Clogged air filter66%
Damaged intake boot54%
Wiring or connector fault42%

Diagnostic Confidence

MAF sensor88%
Air filter78%
Intake boot68%
IAT sensor58%

Use this as a starting point, not a replacement for testing.

Recommended Diagnostic Workflow

1Inspect intake ducting and air filter
2Check for unmetered air leaks
3Review MAF grams-per-second data
4Clean MAF sensor with approved cleaner if dirty
5Test circuit power, ground, and signal

Mechanic's Tips

Tip #1

Start with freeze-frame data and check for related codes. Do not replace components until power, ground, signal, and mechanical causes are verified.

Common Mistakes to Avoid

✕ Replacing parts before testing power, ground, and signal circuits✕ Ignoring related codes and freeze-frame data✕ Skipping the visual inspection✕ Clearing codes before confirming the repair

Common Repairs

Clean MAF sensor

Success Rate: ★★★☆☆

Average Cost: $80-$450

Labor: 0.3-1.2 hours

Replace MAF sensor if testing confirms failure

Success Rate: ★★★☆☆

Average Cost: $80-$450

Labor: 0.3-1.2 hours

Replace cracked intake boot

Success Rate: ★★★☆☆

Average Cost: $80-$450

Labor: 0.3-1.2 hours

Replace air filter

Success Rate: ★★★☆☆

Average Cost: $80-$450

Labor: 0.3-1.2 hours

Parts Commonly Replaced

MAF sensorAir filterIntake bootIAT sensor

Tools Used During Diagnosis

OBD-II scan toolDigital multimeterBasic hand toolsManufacturer service information

Related Repairs

Diagnostic workflowComponent testingWiring inspectionRepair estimate checklist

How to Explain This to Your Customer

P0104 points to the air measurement system. If the computer cannot measure incoming air correctly, fuel delivery and drivability can suffer.

Manufacturer Notes

Generic OBD-II definition. Testing steps and known failures may vary by make, model, engine, and calibration.

Technician Notes

Start with freeze-frame data and check for related codes. Do not replace components until power, ground, signal, and mechanical causes are verified.

Related Codes

P0100 P0101 P0102 P0103 P0110 P0111

FAQ

What does P0104 mean?

It means the computer detected mass air flow circuit intermittent.

Can I keep driving with P0104?

It depends on symptoms. If the Check Engine Light is flashing, the engine is overheating, or the vehicle shifts poorly, stop driving and diagnose it.

Will P0104 fail emissions?

Usually yes if the Check Engine Light is on or readiness monitors are incomplete.

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Editorial StatusGood
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Template Version1.3.4

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Built by mechanics. Improved by mechanics.

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