Car Repairs

Sat, Aug 29, 2009

Gadgets, Home Life

ODB ScannerSo you are driving down the road, all is good… When suddenly…

The check engine light appears on your dashboard.

Ohhh #@$%!!!

Your stomach twists and turns… What could it be? Is my car going to blow up? How much is THIS going to cost me?

You bring it to the mechanic. He tells you the percolator pipe that runs from the condenser to the intake box is bad and needs replacement. Fortunately, he diagnosed it quickly – but it’s going to cost you $1000. A lump begins working it’s way from your stomach to your throat. You rummage through your pocket for that pack of Rolaids that you had to pick up to help settle your stomach, realizing that there is just one left…

You take out your credit card and hand it over, completely at the mercy of this stocky, beer bellied fellow with the letters LOVE and HATE tattooed on the knuckles of each hand.

Does this sound familiar?

Hey, I am not knocking auto mechanics – I know there are plenty reputable shops scattered across the United States. It would just be nice to know at the end of the day if you are being taken for a ride or not.

Enter the OBD reader…

Taken from Wikipedia:

On-Board Diagnostics, or OBD, in an automotive context, is a generic term referring to a vehicle’s self-diagnostic and reporting capability. OBD systems give the vehicle owner or a repair technician access to state of health information for various vehicle sub-systems. The amount of diagnostic information available via OBD has varied widely since the introduction in the early 1980s of on-board vehicle computers, which made OBD possible. Early instances of OBD would simply illuminate a malfunction indicator light, or MIL, if a problem was detected—but would not provide any information as to the nature of the problem. Modern OBD implementations use a standardized fast digital communications port to provide realtime data in addition to a standardized series of diagnostic trouble codes, or DTCs, which allow one to rapidly identify and remedy malfunctions within the vehicle.

I picked up mine at Harbor Freight (I am lucky to have one about 30 minutes from my house – your mileage may vary) for about $90 and it paid for itself almost immediately. Every car has an electrical connector directly under their steering wheel. By plugging an OBD reader into this connector, you can immediately find out the cause for the light. Once you have the code, a little Googling will tell you exactly what is wrong.

The check engine light on my girlfriend’s Altima went on one day. The code indicated a camshaft sensor. We contacted the dealership for an estimate and was told between $350 and $400 dollars. I was able to buy the sensor for $125 and installed it myself – it turned out the sensor was right at the top of the engine and was held in by one bolt. Fifteen minutes and another five minutes to wash my hands and the job was done. Wait, let me correct that. It was twenty minutes – I had a helluva time trying to pull the wire harness from the sensor. By the way, if you haven’t searched and found a forum specializing in your specific car you are crazy. No matter what the car, rest assured there is a forum of average people and mechanics looking to help you fix your car. For my car, I visit Bimmer Forums. The have thousands of posts archived and with a little searching, you can find out a solution to just about any problem.

Don’t get me wrong – there is a time and a place for a mechanic. Trust me, I am not going to try to tackle a transmission job. But for something described above, why wouldn’t I want try to save myself a few bucks – not to mention the inconvenience of having to leave my car at a shop for the day.

Let me throw you another story:

When I bought my car (which was used), within the first 30 days the check engine light came on and I immediately called the dealership. I had already determined that the cause of the light had to do with the transmission. Unfortunately, the fix for this problem ranged from a fuse to a sensor to a torque converter replacement. I never let on to the dealership that I had already checked the codes. I brought the car in and they called me later that day.

“Hello sir. We checked the car and there could be something wrong with the transmission. We are going to change and sensor and have you pick it up. If the light comes on again, we may need to keep the car for a few days.”

They changed the sensor and I picked the car up. Sure enough, a few days later the check engine light came on again. I brought it back it and again they called me at the end of the day.

“Hello sir. Sorry about this, but we are going to have to keep the car for a few days. We will need to change the torque converter.” (which, after checking with Bimmer Forums, was a $1500 job)

In the end, they took care of everything and I knew they were being honest.

In my opinion, the $90 I spent on the reader paid for itself two to three times over. Not to mention that I have become the resident “diagnostic dude” with my friends.

What about you? Do you have a OBD reader? Any good stories to share?

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