We Avoided an Expensive Visit to the Mechanic

About a week ago I was driving my 2000 Toyota Tacoma truck with my seven year old daughter riding shotgun.  We were heading over to my mom’s house for a short visit, which required us to drive across a valley, up a pretty steep, long hill and then along the Puget Sound for a bit.  As we started up the long hill my truck started “pinging” more than it had in the past and I heard my daughter say, “Uh oh dad!”.  I looked down at the dash and there, shining brightly at me, was the “check engine” light.

From my experience, I knew this wasn’t a “pull over right now!” warning but it was telling me that something was wrong.  My first suspicion was that all the pinging had triggered a sensor that was trying to tell me that the engine wasn’t running well and it needed to be looked at.  The rest of the trip was uneventful with the exception of the check engine light.  Once I got home, I decided to reset the light and see if maybe it was just a fluke.  (To reset the light all I had to do was disconnect the negative battery terminal to reset the computer).  With the light off, I pretty much forgot about it.  About two days ago I was heading back over to my mom’s when I approached the same hill.  As we started up the hill, the pinging returned and so did the check engine light.  Ugh.

I was considering calling the dealership but then decided maybe I would be better off just stopping by Autozone to have them hook up their error code reader to the ODBII plug under the dash to find out what the computer was trying to tell me.  I knew they’d at least be able to give me the error code so that I could “Google” it and find out what the vast powers of the Internet could tell me about it.  It only took the reader a few seconds to bring back an error code of P0171.  I thanked the guy and headed home.  After spending a bit of time reading about it, I found that the most likely cause was a dirty air flow sensor.  This is the sensor that sits upstream of the air filter and measures how much air is flowing in to the engine so that the fuel injection computer can tell the fuel injectors how much fuel to shoot in to the cylinders.  I went out and located the sensor on my truck and then unscrewed it to see if there were any signs of dirt on it.  Sure enough I could see a light coating of “crud” on it.  I used some brake cleaner (it was all I had) and the dirt came right off.  I skeptically (I mean, when is the last time someone had this easy of a time fixing their vehicle???) reinstalled it on the truck and put everything back together.  To my surprise the truck ran BEAUTIFULLY.  Seriously, this truck hasn’t run this good the entire time I’ve owned it.

By spending a little time investigating this, I was able to save myself hundreds of dollars.  The total cost to fix this was ZERO.  (Okay, I used a few squirts of brake cleaner but I’ve had that in the garage for 5+ years so I’m not going to count that).  Little victories like this really make me happy!