Hard Brake Pedal Diagnosis
The brake pedal is consistently hard, indicating a loss of power brake assist. This is often due to a failed vacuum booster, a vacuum leak, or a faulty check valve.
Diagnosis Details
Possible Causes
Failed brake booster (vacuum leak or internal diaphragm rupture)
Brake booster vacuum hose or check valve leak/collapse
Faulty master cylinder (internal bypass or blockage)
Related OBD-II Codes
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What You Should Do
Inspect the vacuum hose and check valve for cracks or leaks.
Test the brake booster by pumping the pedal with the engine off, then starting the engine; the pedal should drop slightly.
If not, replace the booster.
Also check for vacuum at the booster port.
Related Repairs
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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.