The Quick Answer above is the generic definition. What follows is the model-specific detail for the Honda models that log P0506.
DTC/P0506·Honda
P0506 on Honda: Causes, Symptoms and Fix Cost
Quick Answer
Moderate SeveritySafe to drive (short-term)Honda
P0506 on a Honda means the engine is idling at a lower RPM than the ECU expects, typically 100 RPM or more below target, and the ECU cannot bring it back up. The opposite of P0507, this code is usually caused by carbon buildup on the throttle body restricting airflow, a partially clogged idle air control passage, or a vacuum hose pinched or blocked rather than leaking.
Typical repair cost, all makes€5 - €550
Connect any standard Bluetooth OBD2 adapter to your Honda and Skanyx tells you what P0506 means on that engine, whether it is safe to keep driving, and what the fix should cost. Free on iPhone and Android.
Get Skanyx freeWhat does P0506 mean on a Honda?
Honda Civic
2006-2015The eighth-generation Civic with the R18A uses a drive-by-wire electronic throttle body, so there is no separate idle air control valve to clean. A low idle usually traces to carbon in the throttle bore or to lost idle adaptation. Clean the bore, then let the engine idle with the air conditioning off until the adaptation relearns.
What causes P0506 on a Honda?
Beyond the generic causes listed on the main P0506 page, these are the patterns noted for Honda models:
Honda CivicCarbon deposits in the electronic throttle bore on R18A
Honda CivicIdle adaptation lost after a battery disconnection or throttle body cleaning
How to diagnose P0506 on a Honda with OBD2
Follow these steps to pinpoint the root cause of P0506:
- Read freeze-frame data and confirm idle RPM at the time the code set. Engine RPM is standard OBD2 live data; the ECU's commanded idle target usually needs manufacturer-level software
- Remove the intake boot and inspect the throttle plate and bore for carbon buildup. Heavy deposits restrict airflow even with the plate fully closed
- Clean the throttle body with throttle body cleaner and a soft cloth. On electronic throttle bodies, do not force the plate open by hand; open it with the ignition-on procedure or an output test in manufacturer-level software instead
- If equipped with a separate idle air control valve, remove and clean it, then check that it moves through its full range (an output test usually needs manufacturer-level software)
- After cleaning, perform the manufacturer's idle or throttle relearn procedure (on many cars this is an adaptation run with manufacturer-level software). Without a relearn, the ECU continues to command the same restrictive throttle position
How much does P0506 cost to fix on a Honda? (EUR)
Estimated repair costs for P0506 in EUR, compiled across makes. Honda parts and labour usually land towards the lower end of each range.
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
Codes related to P0506
These codes are often seen alongside P0506 or point to related issues, on any make:
Looking for the full P0506 reference (all makes, full diagnosis flow, complete repair cost matrix)?
See the main P0506 guideSkanyx · Honda
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