Auto Diagnostic

Precision Diagnostics for Engines, Fuel Systems, and Electrical Issues

When your vehicle isn’t running properly or warning lights appear on the dashboard, it’s time for professional diagnostics. At National Restorations, LLC, we offer accurate and affordable auto diagnostic services to help identify problems quickly and correctly. Based in Queenstown, MD, our team uses up-to-date tools and years of mechanical experience to locate faults in your engine, ignition, fuel, and electrical systems.



We specialize in diagnostics for light-duty trucks, personal vehicles, and work vehicles. Whether you’re experiencing performance issues, unusual noises, or starting problems, we get to the source without guesswork. Our diagnostics give you a clear understanding of what’s wrong and what it will take to fix it — with no pressure and no hidden costs.

When to Schedule Diagnostic Services

You don’t have to wait for a total breakdown to bring in your vehicle. If something feels off, chances are it’s worth checking out. Common reasons to schedule a diagnostic test include:



  • Check engine light is on
  • Engine running rough or stalling
  • Hard starting or no-start conditions
  • Poor fuel efficiency
  • Loud or unusual engine sounds
  • Loss of power while accelerating
  • Warning lights for emissions, ABS, or battery systems


Even minor issues can signal larger underlying problems. Our team will isolate the cause and walk you through what’s happening and why.

What Our Auto Diagnostics Include

Our diagnostic process is designed to be thorough and efficient. We check every major system that could affect engine performance and drivability. Our service includes:



  • OBD-II scan (onboard diagnostics)
  • Real-time engine data analysis
  • Ignition system testing
  • Fuel injection system checks
  • Battery and alternator evaluation
  • Spark plug and coil performance review
  • Electrical fault tracing and circuit testing


In most cases, we can complete a full diagnostic in one visit and provide a clear, written report outlining the issue and potential repair options.

Engine and Performance Troubleshooting

Many common performance problems — like low power, poor idling, or reduced fuel mileage — are connected to issues in the ignition, fuel, or emission systems. We use computer-assisted tools combined with real mechanical inspection to pinpoint the problem accurately.

Typical issues we uncover include:



  • Dirty fuel injectors
  • Faulty ignition coils
  • Bad spark plugs or wires
  • Clogged fuel filters
  • Vacuum leaks
  • Oxygen sensor failure
  • EGR valve malfunction


We’ll identify whether a part needs cleaning, adjustment, or full replacement — and explain the options in plain terms.

Diagnostics for Light-Duty Trucks and Work Vehicles

In addition to personal vehicles, we offer diagnostics for light-duty commercial trucks, vans, and work vehicles. If your fleet truck or service vehicle is having issues, our team can evaluate:


  • Engine misfires
  • Transmission warning lights
  • Electrical system irregularities
  • Idle control or throttle body problems


Minimizing downtime is critical for your business, so we provide fast, focused diagnostics to get your vehicle back on the road as soon as possible.

What Sets Us Apart

At National Restorations, we don’t rely on just computer codes. We combine scan tool data with hands-on inspection to understand what’s really happening with your engine or electrical system. Our technicians explain problems clearly and never push unnecessary repairs.



Why customers trust our diagnostic services:


  • Accurate testing using current equipment
  • Clear explanations and printed reports
  • Fast turnaround and fair pricing
  • Diagnostics only — no pressure to commit to repairs
  • Trusted by locals throughout Queenstown and surrounding areas


We work for your confidence, not your confusion. If you’re unsure what’s going on with your vehicle, we’ll give you straight answers.

Schedule a Diagnostic Appointment

If your vehicle is showing signs of a problem — or you just want peace of mind — schedule an appointment with National Restorations today. We’ll run a complete diagnostic check and help you make an informed decision about your next steps.