P0507 on a 2017 Honda Civic
Idle Higher Than Expected
What does P0507 mean on a 2017 Honda Civic?
P0507 is set when the ECM commands the throttle to a specific idle RPM and measures actual idle higher than that target by more than a calibrated amount (typically 200+ RPM higher). The cause is almost always unmetered air entering the engine — a vacuum leak somewhere — or a stuck throttle body / idle control issue.
Symptoms on a 2017 Honda Civic
- Check Engine Light is illuminated
- Engine idles noticeably high (1000-1500 RPM instead of 700-900)
- Possible whistling or hissing sound from the intake area
- Reduced fuel economy
- Hesitation as the engine tries to slow when stopping
- May be paired with P0171 (lean code)
Likely causes on a 2017 Honda Civic
- Vacuum leak (intake gasket, PCV hose, brake-booster hose, throttle-body gasket) Most commonEstimated repair: $80– $600
Most P0507 codes trace to unmetered air entering the engine.
- Carbon-coked throttle body keeping the blade slightly open CommonEstimated repair: $20– $200
- Failed or sticking idle air control (IAC) valve on older non-ETC vehicles CommonEstimated repair: $80– $300
- Failed throttle body needing replacement and relearn OccasionalEstimated repair: $250– $800
- Sticking accelerator pedal or throttle cable (older vehicles) OccasionalEstimated repair: $50– $250
- Cracked plastic intake manifold OccasionalEstimated repair: $250– $900
- EVAP purge valve stuck open (often sets P0496 alongside) OccasionalEstimated repair: $80– $300
How to diagnose this on a 2017 Honda Civic
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Confirm the actual idle RPM and check fuel trims
Scan-tool live data should show actual idle RPM and the target. Look at Bank 1 LTFT: a high positive number (e.g. +15 % or more) confirms a real vacuum leak. Trims near zero with high idle point at a throttle body or EVAP issue rather than a leak.
Tools: Scan tool with live PIDs
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Smoke-test the intake
Pressurize the intake with smoke through a snorkel cap or the throttle body. Watch every gasket, hose, vacuum tee, the brake booster line, the PCV system, and the EVAP purge line. Smoke escaping anywhere is the leak.
Tools: EVAP / intake smoke machine, Flashlight and inspection mirror
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Inspect and clean the throttle body
Coked carbon at the throttle bore prevents the blade from closing fully — the engine pulls air around the blade that the ECM cannot fully control. Clean with throttle-body-safe cleaner (never carb cleaner) and a soft brush. Perform an idle relearn after.
Tools: Throttle body cleaner, Soft brush, Service manual for the relearn procedure
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Test the IAC valve (non-ETC vehicles)
On older vehicles with a separate IAC valve, command the valve with a scan tool and watch for idle changes. A valve that does not respond, or that idles correctly with the connector unplugged, is stuck or failed.
Tools: Scan tool with IAC command
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Verify the EVAP purge valve is not stuck open
A stuck-open purge valve introduces unmetered fuel vapor at idle, causing high idle and lean trims similar to a vacuum leak. With the engine idling, disconnect the purge valve — if idle smooths out, the purge valve is the cause.
Tools: Hose disconnect tools
Known Technical Service Bulletins for the 2015-2019 Honda Civic
Manufacturers publish Technical Service Bulletins (TSBs) when a known issue affects a specific vehicle. These bulletins come from the NHTSA database for your Honda Civic.
- ENGINE Jul 27, 2025
Service Bulletin - Oil leak at timing chain tensioner inspection cover due to possible insufficient sealant adhesion on inspection cover.
NHTSA #11021745 - FUEL/PROPULSION SYSTEM Aug 5, 2024
Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2020 Accords, 2016-2020 Civics, 2017-2020 CR-Vs, & 2018-2020 Odysseys that have been diagnosed to be in need of the low-pressure fuel pump, fuel strainer, fuel meter or fuel tank replacement.
NHTSA #11006249 - FUEL/PROPULSION SYSTEM Jul 21, 2024
Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2020 Accords, 2016-2020 Civics, 2017-2020 CR-Vs, & 2018-2020 Odysseys that have been diagnosed to be in need of the low-pressure fuel pump, fuel strainer, fuel meter or fuel tank replacement. If you have a vehicle that match the qualifiers listed below, AHM requests to have the photos of the lock ring & the low-pressure fuel pump flange taken & sent to TIS (click HERE for example photos).
NHTSA #11005271 - FUEL/PROPULSION SYSTEM Jul 5, 2024
Dealer Message - Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2020 Accords, 2016-2020 Civics, 2017-2020 CR-Vs, & 2018-2020 Odysseys that have been diagnosed to be in need of the low-pressure fuel pump, fuel strainer, fuel meter or fuel tank replacement.
NHTSA #11004264 - VISIBILITY/WIPER Jun 18, 2024
Service Bulletin - Due to a new North America regulation which introduces a new refrigerant and oil requirement, the compressor shaft seal may leak. American Honda is extending the warranty on the A/C compressor shaft seal from the original 3 years to 10 years from the original date of purchase, with no mileage limitation. The new refrigerant and oil may cause swelling of the compressor shaft seal. The swelling may lead to abnormal wearing of the seal which may increase seal gaps around the compressor shaft allowing refrigerant to leak out.
NHTSA #11002711 - VISIBILITY/WIPER Jun 18, 2024
Service Bulletin - American Honda is extending the warranty on the A/C condenser to 10 years from the original date of purchase with unlimited miles. This warranty extension only covers vehicles that have a defective A/C condenser from the factory. The A/C condenser was not manufactured to specification. As a result, corrosion may develop in the form of tiny holes in the condenser tube walls that allow the refrigerant to leak out.
NHTSA #11002705
+14 more TSBs available in MECH AI's TSB explorer for this vehicle.
Common fixes
- Repair vacuum leak(s) found by smoke test
- Clean the throttle body and perform idle relearn
- Replace the IAC valve (older vehicles)
- Replace the EVAP purge valve
- Replace cracked plastic intake manifold (model-specific)
About the 2015-2019 Honda Civic
The 2015-2019 Honda Civic was commonly sold with the following powertrains: 2.0L I4, 1.5L Turbo I4, 1.8L I4. Common trims include LX, Sport, EX, Touring.
The vacuum leak almost certainly is the cause
P0507 paired with P0171 (or P0174) is virtually always a vacuum leak. The high idle and the lean fuel trim both result from the same underlying problem: unmetered air entering the engine downstream of the MAF. The ECM cannot identify exactly which leak path is responsible, only that one exists. Smoke testing is the fastest path to the source.
Common P0507 leak locations by engine
- Ford 4.6 / 5.4 modular V8 — cracked plastic intake manifold, PCV hose at the rear of the engine
- GM 3.6 LFX / LLT V6 — intake manifold gaskets, PCV system
- Toyota 2GR-FE V6 — throttle-body gasket, intake plenum bolts
- Honda K-series — IACV gasket, vacuum tee at the brake booster
- Chrysler 3.5 / 3.6 Pentastar — PCV tube, intake gasket
- Most vehicles 10+ years old — hardened brake-booster hose
Idle relearn after throttle body cleaning
Modern vehicles with electronic throttle control require an idle relearn after any throttle body removal, cleaning, or replacement. The procedure varies — generally:
- Battery disconnect 30+ seconds, reconnect
- Key on, engine off, 30 seconds
- Start engine, idle 5 minutes with no load (AC off, no electrical accessories)
- Drive a short cycle including a few full stops
Some vehicles require a bidirectional scan tool to perform the relearn. Without a successful relearn, P0507 will set again within a few drive cycles even though the throttle body is mechanically perfect.