What is OBD-II and does my car support it?

OBD-II (On-Board Diagnostics II) is a standardized system in all cars manufactured after 1996 in the US and 2001 in the EU. If your car was built after these dates, it almost certainly has an OBD-II port, typically located under the dashboard near the steering column.

How does GaugeAI diagnose car problems?

GaugeAI uses advanced AI models trained on millions of diagnostic records to analyze your OBD-II error codes, sensor data, and vehicle information. It cross-references manufacturer-specific databases to provide accurate, plain-English explanations and repair recommendations.

What OBD-II scanners are compatible with GaugeAI?

GaugeAI works with any ELM327-based Bluetooth or WiFi OBD-II scanner. Popular options include BAFX Products, Veepeak, and BlueDriver. You can also upload data manually through photos, CSV files, or raw diagnostic logs.

Is GaugeAI accurate enough to replace a mechanic?

GaugeAI achieves 99.2% accuracy in code interpretation and provides detailed repair guidance. While it is an excellent first-line diagnostic tool that can save unnecessary mechanic visits, we recommend professional inspection for complex repairs and safety-critical issues.

Which car brands and models does GaugeAI support?

GaugeAI supports over 10,000 vehicle models across all major manufacturers including Toyota, Honda, BMW, Mercedes-Benz, Ford, Chevrolet, Hyundai, Kia, Volkswagen, Nissan, Changan, and many more. Our AI is trained on manufacturer-specific diagnostic data for more precise results.

How much does GaugeAI cost?

GaugeAI offers a free plan with 5 diagnostic scans per month. Our Pro plan at $14/month includes unlimited scans, full diagnostic history, repair cost estimates, and priority AI analysis. Fleet plans start at $89/month for businesses managing multiple vehicles.

Is my vehicle data secure and private?

Absolutely. All diagnostic data is encrypted in transit and at rest using AES-256 encryption. We never share your vehicle data with third parties. You can delete your data at any time from your account settings. We are SOC 2 Type II compliant.

Can I use GaugeAI without an OBD-II scanner?

Yes. While direct OBD-II connection gives the most comprehensive results, you can also upload photos of your dashboard warning lights, paste error codes manually, upload CSV data exports from other tools, or share scanner screenshots for AI analysis.

Medium SeveritySafe to Drive

What does P0505 mean?

Idle Control System Malfunction

Direct Answer

P0505 means the idle air control (IAC) system is not maintaining the target idle speed. The IAC valve (or electronic throttle on drive-by-wire systems) regulates airflow at idle to keep the engine at a stable RPM regardless of electrical load, A/C, and temperature.

Common Symptoms

✓Check engine light on
✓Rough, fluctuating idle (RPMs hunting up and down)
✓Engine stalling at idle, especially when cold
✓High idle that will not come down
✓Low idle that stalls when accessories are turned on

Common Causes

01Dirty or failed IAC valve
02Vacuum leak (extra air bypasses IAC control)
03Carbon buildup on throttle body
04Faulty throttle position sensor
05Failed electronic throttle body (drive-by-wire vehicles)

How to Fix P0505

Clean the throttle body and IAC valve

Remove the air intake hose and spray throttle body cleaner inside the throttle bore while the engine is off. Clean the IAC valve passage. Carbon buildup is very common after 60,000+ miles.

Check for vacuum leaks

An unmetered air leak causes erratic idle that the IAC cannot compensate for.

Test the IAC valve

On many vehicles you can command the IAC valve through a scan tool. If it does not respond, check wiring or replace the valve.

Perform throttle body relearn

After cleaning or replacing throttle body components, a throttle position relearn may be required with a scan tool.

Frequently Asked Questions

Why does my idle fluctuate after cleaning the throttle body?

Many modern vehicles require a throttle position relearn after the throttle body is cleaned or replaced. The ECM needs to recalibrate the baseline throttle position. This can often be done by disconnecting the battery for 30 minutes, or through a scan tool idle relearn procedure.

Estimated Repair Cost

$20–$700

Throttle body cleaning: $20–$100 DIY. IAC valve: $30–$150. Electronic throttle body: $200–$700.

Safe to Drive?

Yes — with caution

Use caution. The engine may stall at traffic lights or when coming to a stop.

Related Codes

P0506P0507

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