Auto Part Stores Engine Code Awareness

We get many customers that have had there check engine light diagnosed by Auto Part stores. These stores are very convenient and do a good job at reading the most common problem. This is the problem. The most common problem does not mean it is the only problem or the exact problem. For example we had a customer that had several misfires and the printout given to them for the most copmmon problem was to have spark plugs replaced. Although that is one possibility the code also can reflect a bad ignition coil. We scanned the car with our scanner and found misfires on 5 of the 6 cylinders. The chances of 5 spark plugs going bad is very , if not completely impossible. The codes could as easily meant 5 of 6 coils were bad, which too is not very likely. In some cars there is the possiblity of one main coil , in those cases the coil may be that bad. This car had 6 individual coils. I called the customer to let them know I was not sure that plugs were the answer. They informed me that they were told by ” the Auto parts store” it was plugs and we must be looking for something or how can our scanner show more. This is when it gets hard to convince customers that maybe our scanner is better and we are not trying to get more done. In fact at All Kar I will usually let customers know so that they can change what they wanted done in an effort to save them the cost and aggravation of a part not needed. We do not charge to recheck the codes, and we encourage customers to be with us when we do it. Customers need to know that the most common problem is not the only problem. There is a reason that we are experienced mechanics and are not just a parts salesman.

Last week I had a customer tell me that since the E-Check gave her the codes that were part of her E-Check failure the problem is what the code said. In this case there was a Tire Speed Sensor code. She wanted a price on installing sensors. Sensors are all different prices and her’s were more expensive then most. She said that it is just a wire and why so much. We do not set the price. I did tell her that she should bring her car down so that we can make sure it is not a bad wire, tone wheel, magnet, or hub bearing. She insisted that because the code said wheel speed sensor it was the sensor itself. She explained that the “person” from the E-Check facility said that these were the codes and she should avoid going to get it diagnosed and paying for what was already showing. First off, we NEVER try to get someone in for a cost just to diagnose. Our goal is to make sure the right repair is made, that’s all. She then mentioned that she needed Two Camshaft sensors and one Crankshaft sensor. That seems a bit strange and there might be more going on. Again she thought that whatever it said was the only thing it can be. Once again the codes are a guide to help mechanics find a problem. Sometimes the code will be right on. Sometimes a sensor, for example, can throw a code because another part in the system is not sending it the right signal. I am wriuting this so that people can be aware that because they received a code with the explanation of the most common problem, it can be more then it appears. Sometimes the real problem is better then the most common problem. In the case of the spark plugs, the customer told me to repair what they found” Oh and what the read on Google, they car still idled rough, they said that they would take it somewhere else to get looked at. We can only make repairs based on many years of experience, that is why we are mechanics. My personal guess is that they will find a vacuum leak or injector problems. Plugs and coils do not go several at a time. But what do we know , the parts guy told them differently.

However there are shops out there that will charge for the right diagnosis. All we do is read the codes and make sure the customer does not waste their money. In the end if we do not inform them on what might be a mistake, we are to blame when the car winds up with the same problem.