The Magic Box


Two times today I had calls from customers wanting an estimate and they were concerned because we charge a fee to test before we do any actual repairs. One wanted to know why their car’s check engine light was on, especially as the car was running just fine. They said a neighbor came over and offered advice and a diagnosis of what he thought the problem might be.

I appreciate the helpfulness of friends, neighbors and tow truck drivers as they care enough to try to figure out what a car problem might be. Many times they have been right but just as many times they have been wrong. Whatever their diagnosis might be…it is still just a guess! Professionals (whether it is an auto repair shop, home air conditioning repair, the dentist or doctor), would never give a diagnosis or attempt “a repair” without first testing circuits, components or in humans taking temperatures, blood pressure, drawing blood, taking x-rays and more to see what the problem really is.

The customer then asked me to “just plug in that box” that tells you what’s wrong with the car. I am to this day puzzled why so many people believe there is a “magic box” that we plug into a car that tells us what is wrong with the car! If that “magic box” were available, I would buy several and I would not need a staff of expert technicians who have years of experience, training, and over $20,000 worth of tools and equipment.  That would greatly reduce my payroll and operations cost. I could just hire low paid mechanics to replace the parts the “magic box” said were bad. I wish our business was that easy.

Please believe there is no “magic box”, but there is a scan tool that gathers information and data to point the technician in the right direction to test the circuits and components that may have failed.

What has happened over the years is many inexperienced shops or mechanics plug in the scan tool and retrieve a code. The code is what lets the technician know what item(s) need to be tested.  Here is an example. A PO300 means a random misfire has occurred in the engine. With this code alone many shops will sell you spark plugs, clear the code and hope it is fixed without any testing fee. Sometimes you get lucky and it fixes the code, other times the light returns in a few days to a week and they sell you more parts (We call these shops “parts replacers” and they keep replacing and charging their customers until they finally get it right).

Most professional shops will charge a fee to test items such as fuel pressure, the fuel injectors, coils, all the sensors, vacuum leaks, fuel trims, spark plugs and other items related to the code. Once testing is complete, an accurate repair can be performed, saving you time and money, because the concern is fixed the first time and there is no need to return for more parts.

As cars become more computerized, the systems are more difficult to test! Please beware of anyone that will just replace parts and not test to identify the concern.

Have a great day.

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