Check Engine Light

A modern vehicle has more on-board computing power than the Apollo spacecraft that went to the moon!

The application of computer controlled fuel and emission systems has increased our fuel mileage, horsepower per liter and cleaned up our air. It is truly an improvement over the carburetor of yesterday.

The 1970 fully equipped Cadillac weighed 4409 lbs. It had a 7.7L engine with 288 horsepower and got an average of about 10mpg. The 2012 Cadillac weighs 3900 lbs and has a 3.6L engine delivering 318 horsepower and 22 mpg!

The computer in modern cars controls the a/c system, windows, fuel, emissions, transmission, brakes, navigation and many other systems. Eventually, cars will drive themselves enabling the driver to watch TV or surf the net while going to work. Until then, your car’s check engine light let’s drivers know when it is time to schedule engine service. The light can mean any number of things, from something so small as a loose cap or something worse like an alternator issue. That is why it is best to get your vehicle to a technician as quick as you are able. If you currently see your check engine light in Austin, TX, call us today at (512) 326-3474. Let our mechanics show you the Leonard’s Garage difference.

Fuel Delivery System

The computer system for fuel delivery is basically comprised of the main computer called the Electronic Control Module or ECM and various sensors. The ECM is fed information from various sensors located in the engine and exhaust systems.

The sensors related to fuel delivery monitor data from the engine, such as the position of the throttle, the amount of air coming in the engine, the hydrocarbons of the exhaust, the coolant temperature, the position of the crankshaft and camshaft, the outside air temperature and many others. The sensors feed the data back to the ECM and the computer measures the proper amount of fuel needed at that time.

Diagnosing The Check Engine Light

The check engine light is the warning light for the system. It is an orange light that usually displays “check engine” or “service engine soon”. When the light is on, it lets you know the computer has detected a malfunction with a sensor in the system.

When diagnosing a malfunction in the system, it is important to remember the codes provided by the computer do not “tell you what’s wrong” with the system. The code tells the diagnostician what the condition is. For instance, the code may indicate a “lean burn” condition. This can be caused by many different things and the components must be checked individually.

One condition that we often see is easily corrected by the vehicle owner and that’s the gas cap. A loose gas cap will trigger the check engine light. It should be the first thing checked. If the cap is loose, tighten it and drive the car a few days. If the light doesn’t go off, it may need to be reset by a professional.

Specialized testing equipment is needed to properly diagnose the system, and as cars become more sophisticated, so does the technical training and equipment. To stay up to date, we make sure all of our technicians undergo training on all makes and models. Our training program the best in the area, and all our technicians are ASE certified to work on all vehicles.

The other computer control systems have their own modules and sensors. These modules and sensors replace a whole host of heavier parts like actuators, vacuum pots, vacuum accumulators, vacuum hoses and so on. This has resulted in lighter, more fuel efficient cars and trucks.

If your car’s check engine light has come on, schedule your engine service with Leonard’s Garage today! Our technicians will diagnose and repair the cause of your check engine light in Austin, TX. Give us a call at (512) 326-3474!