6935 Overland Rd.

Boise ID

208-906-3734

Official Certified Ada County Emission Testing #181

E-mail Ace Emission



Today’s vehicles are highly sophisticated and highly efficient.  All 1966 and newer cars and trucks have an advanced powertrain control computer that uses second generation on-board diagnostics (OBD-II) technology to manage and monitor the operation of the engine, transmission and emissions control components.

How Do I Know the OBD System Is Working Correctly?

When you turn on the ignition, the “Service Engine Soon” or “Check Engine” light should flash briefly, indicating the OBD system is ready to scan your vehicle for any malfunctions.  After this brief flash, the light should stay off while you drive as long as no problems are detected.

What does it mean if the light turns on while I’m driving?

If the light comes on and stays on, the OBD system has detected a problem.  Your vehicle might have a condition that wastes fuel, shortens engine life, or causes excessive air pollution.  If left unadd3essed, these conditions could also damage your vehicle and lead to increasingly expensive repairs.  For example, OBD can identify a loose or missing gas cap (which wastes fuel and contributes to smog)  or engine misfire (which can lead to severe or permanent engine damage).

What should I do if the light stays on?

What does it mean if the light is blinking?

If the light is blinking, a severe engine problem such as a catalyst-damaging misfire is occurring and should be addressed as soon as possible.  You can still drive safely, but should minimize your time on the road.  Try not to drive the vehicle at high speed or with excess weight (such as towing or carrying heavy equipment).

What will my technician do when I take my vehicle into the shop?

As your repair shop if they employ trained OBD  technicians.  A modern repair shop or dealership should have an OBD scan tool to diagnose the cause of your vehicles problem.  These technicians will have the proper tools and will know best how to diagnose your vehicle.

The technician will connect a small, hand-held scanning device to your vehicle’s computer (usually through a connector under the dashboard) and download information that can pinpoint the problem.  The technician can then repair the vehicle based on manufacturer recommendations.  OBD actually helps repair technicians to their job more quickly and reliably, helping you avoid unnecessary repairs and trips back to the shop.

What should I do if the light goes out before I take the vehicle to the shop?

Usually, nothing.  If the problem that caused the light to come on is addressed, the OBE computer will turn the light off.  This is not an indication of a faulty OBD system.  In act, the system is doing its job by verifying that a problem temporarily existed but has since been corrected; perhaps a loose gas cap was tightened or fouled spark plug was cleared.  Your vehicle needs no special attention unless the light comes on again.

What else can I do to  make sure my vehicle is running well and to minimize its environmental impact?

ODB helps to ensure today’s vehicles are running in top shape and at the peak of efficiency, but you still need to maintain your vehicle according to the manufacturer’s recommended schedule.  Keep up with routine maintenance and keep an eye out for your Check Engine light. Always turn off the engine before refueling and always make sure the gas cap is securely tightened.  You’ll save money on fuel and repairs while helping to do your part to protect the air you breathe.  In addition driving as little as possible by combining trips, carpooling, walking biking or using public transit are all things you can do to help minimize vehicle pollution.