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.

High SeverityDo Not Drive

What does P0301 mean?

Cylinder 1 Misfire Detected

Direct Answer

P0301 means the ECM detected a misfire specifically in cylinder 1. Unlike P0300 (random misfire), P0301 points directly at the first cylinder, making diagnosis faster — you can immediately focus on the spark plug, coil, and injector for that cylinder.

Common Symptoms

✓Check engine light on (possibly flashing)
✓Strong vibration at idle
✓Stumbling or lurching when accelerating
✓Possible popping sound from engine

Common Causes

01Worn or fouled spark plug in cylinder 1
02Faulty ignition coil on cylinder 1
03Clogged or dead fuel injector on cylinder 1
04Low compression in cylinder 1 (burned valve, worn rings)
05Vacuum leak near cylinder 1 intake runner

How to Fix P0301

Swap the cylinder 1 coil with another cylinder

Move the coil from cylinder 1 to cylinder 2 and clear codes. If the misfire moves to P0302, the coil is faulty. If P0301 stays, the coil is fine.

Replace the cylinder 1 spark plug

Pull the plug and inspect. A worn, cracked, or fuel-fouled plug is the most common cause. Replace and retest.

Test cylinder 1 injector

Swap injectors between cylinders or use a noid light to verify injector pulse. No pulse = wiring or ECM issue. Pulse but no spray = clogged injector.

Compression test on cylinder 1

If ignition and injection check out, measure compression. Below 120 psi (or 25% lower than adjacent cylinders) indicates internal engine damage.

Frequently Asked Questions

How do I know which cylinder is cylinder 1?

Cylinder 1 is typically the frontmost cylinder on inline engines, or the front cylinder on the driver's side (Bank 1) on V6/V8 engines. Check your owner's manual or a model-specific diagram.

Estimated Repair Cost

$30–$1500

Spark plug: $10–$50. Coil: $50–$200. Injector: $150–$400. Compression repair: $800–$1,500+.

Safe to Drive?

No — avoid driving

Avoid driving until resolved, especially if the check engine light is flashing.

Related Codes

P0300 P0302 P0303 P0304

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