Check Engine Light is Money Maker for Dealers


Everyone has seen the “Check Engine” light that comes on, to tell the owner of the car that “something is wrong.” Car manufacturers should replace this light with a dollar sign because it's a great money maker for mechanics. When my “Check Engine” light came on I decided I had enough. “I'm not going to do this for the rest of my life. I have to know what's really going on.” Even though my car has an excellent warranty, I decided to do as much work as I could to resolve this situation before bringing it to the dealership. I hate not knowing stuff.


My first step was to educate myself about these new systems in cars. So I went to the university of and spent an evening watching videos about OBD2 (On Board Diagnostics), scanners and where to find the “connection” on modern cars.


Every car, after 1996 has a connector where all garages, mechanics and private individuals can plug in a device to get the whole “dope” on what's going on with their car.We have as much access to the information as any garage has, provided we own a little device called an OBD2 scanner.



One of these devices costs anywhere from $15.00 (from China) to around $500.00.  I purchased one for $120 and I'm glad I did. The OBD2 automobile standard will be with us for a long time; and a piece of equipment like this is really an investment. I expect to use it for many years to come.


Here's what happened to me: The scanner reported an error code of P0455 which is a massive air leak in the pollution control system. I checked the internet and discovered that most people have a defective or leaking gas cap when this code “pops.” So I opened the gas cap door and found my gas cap was loose. The last time I filled up the car, the attendant was too lazy to twist the cap in it's receptacle, but simply left it rattling in the filler compartment, and closed the door. When I tell people this story they always say, “I could have told you that.” But in reality, who would ever guess that such a simple thing could cause that much grief. That gas station attendant (Queen and Lesslie Streets, in Toronto) was probably causing a lot of trouble for most of his customers.

He didn't realize he was making people spend hundreds of dollars getting their cars fixed by unscrupulous mechanics. I spent $120.00 on a device that I really didn't need.


Last time I had my oil changed the mechanic forgot to, or didn't realize he had to, reset the “oil life monitoring system” on my car. That was another evening learning about it on It turns out that your car will remind you to change the oil if you wait too long. If the mechanic forgets to reset this system, a warning light will come on telling you to change your oil even though it is not necessary. Each car has a different reset procedure so you have to do a little “home work” to find out about yours. Unless you are willing to learn a bit about how things work, you are going to be reaching into your pocket to pay other people, that are a little smarter than you, to do the work. This car thing is a real racket.


Richard Roocroft


December 2011


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