Hard Brake Pedal Diagnosis
The brake pedal is consistently hard, indicating a potential issue with the brake booster, vacuum supply, or master cylinder. This reduces braking assist and increases stopping distance.
Diagnosis Details
Possible Causes
Failed brake booster (vacuum leak or internal diaphragm rupture)
Vacuum hose leak or blockage between intake manifold and booster
Faulty master cylinder (internal bypass or blockage)
Related OBD-II Codes
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What You Should Do
Check brake booster vacuum supply with a vacuum gauge (should hold 18-22 inHg).
Inspect vacuum hose for cracks or disconnection.
If vacuum is good, test booster function by pumping pedal with engine off, then starting engine—pedal should drop slightly.
If not, replace booster.
Also check for brake fluid contamination or leaks.
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Disclaimer: This AI-generated diagnosis is for informational reference only. Always consult a qualified mechanic for an in-person inspection. AutOwner is not responsible for decisions made based on this information.
