P0507 — Idle Air Control System RPM Higher Than Expected
P0507 sets when actual idle speed is higher than the target by a calibrated amount. Vacuum testing and proper relearn prevent unnecessary throttle-body replacement. High idle after throttle-body cleaning usually means the relearn was not performed.
Fault Overview
Vacuum leaks, dirty throttle body (sticking open), incorrect idle learn, throttle plate not closing fully, boost leaks on forced-induction engines, and stuck PCV valve are the primary causes.
Engine & Platform Coverage
Symptoms
- •P0507
- •high idle
- •idle speed high
- •IAC high RPM
- •P0507 vacuum leak
- •high idle after cleaning
Possible Causes
- 1.Vacuum leaks
- 2.Dirty throttle body (sticking open)
- 3.Incorrect idle learn
- 4.Throttle plate not closing fully
- 5.Boost leaks on forced-induction engines
- 6.Stuck PCV valve
Wiring & Circuit Notes
Throttle body and APP circuits.
DVOM Specs & Sensor Tests
Target vs actual idle. Throttle position at closed throttle. Vacuum reading.
Diagnostic Flow — FSM Sequence
AI Diesel Tech enforces this evidence-gate sequence. Each gate must pass before advancing.
5 steps locked behind Technician Mode- 1Step 1 — Compare Target vs Actual Idle: Compare target vs actual idle speed on the scan tool.
- 2Step 2 — Smoke-Test for Vacuum Leaks: Smoke-test the intake system for vacuum leaks.
- 3Step 3 — Clean Throttle Body and Perform Relearn: Clean the throttle body and perform the OEM idle relearn procedure.
- 4Step 4 — Verify Throttle Plate Closes Completely: Verify the throttle plate closes completely at idle.
- 5Step 5 — Check PCV System: Check the PCV valve and hoses for sticking or restriction.
- 6Step 6 — Confirm Idle Returns to Normal: Confirm idle returns to the target after repair.
Unlock the full evidence-gated diagnostic sequence, DVOM test steps, and repair procedures in Technician Mode.
Full Diagnostic Access
Verification steps, preventative measures, severity guidance, and legacy comparison are available in Technician Mode.
Typical Repair Costs
Repair vacuum leaks $20–200; clean throttle + relearn $20–80; replace sticking throttle body $150–600.
Related Codes & Pages
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Summary
Use the AI Diesel Tech diagnostic engine to run this code through a structured, evidence-gated sequence and get a confirmed root cause before any parts are replaced.