So my car, 2003 Toyota matrix XR, is just shy of 100K miles and I decided to perform some maintenance.
The first thing I did was to disconnect the negative terminal on the battery. This protects the equipment will I am taking it apart as well as resents the computer if the negative terminal is off for >20 mins. This alows for the car to basically give its-self a tuneup.
The next thing I did was clean the mass air flow (MAF) sensor. This sensor determines the flow rate of air going into the engine and allows the computer to maintain a proper air/fuel ration. The MAF collects junk on the sensors which can interfere with this crucial parameter. To clean it, one only has to remove the sensor from the air intake tube (between the air filter and the throttle body) and spray it down with some mass air flow cleaner or electronics cleaner. I picked up a can of CRC Mass Air Flow cleaner at Advanced Auto Parks for ~$7. On the can it says that it can improve gas mileage and gain 4-10 horsepower. I highly doubt such gains could be made by just cleaning the sensor unless your sensor is ridiculously dirty. Mine didn't look to dirty but there was decent build up.
Here is my cleaned MAF sensor. The amber ball on the side is a temperature sensor and the actual flow sensor down in the plastic tube. Be gentle while cleaning as this part is sensitive and crucial to your car.
Next I replaced my spark plugs. First I removed the plastic engine cover which revealed the individual ignition coils that sit on-top of the plugs as seen below.
After removing the ignition coils, its time to replace the plugs. I bought NGK iridium's from Advanced Auto-parts. The lady at the store said that I did not need to gap them as they came pre-gaped. After some surfing on the web at various forums including
www.matrixowners.com (which is an awesome resource for my car at least) and the manufacturers website, I came to the conclusion that these plugs needed gaped. After another trip to Advanced I got a gaping tool.
For my car, the gap needed to be sent to 1.1mm. The new spark plugs came pre-gaped at 1mm. So a little tweaking later the gaps are set correctly. The gaping tool pictured above was pretty useful and cost less then $2. The round hole provides a fairly easy way to make the gap wider. One has to be careful to no damage the electrodes while gaping.
Next I removed the old plugs and inserted the new plugs.
As can be seen above, the old plugs do not look to bad and I probably could have gotten away with just cleaning them. At any rate, I replaced the plugs (have no idea how many miles are on them). Since my block has an aluminum head on it, it is crucial important to make sure that the engine is completely cooled. Aluminum becomes fairly ductile at high temperatures making it easy to cross thread the spark-plug holes. After hand tightening the plugs (do not use air tools) I used a tourque wrench to torque the plugs to the factory specs.
Making sure the torque is correct on the plugs insures that the plugs will seal the cylinder and that unnecessary stress is not induced by over tightening the plugs. For my car, this torque is 18 ft-lbs.
I was planning on cleaning the PCV valve also however I did not have a deep enough socket to remove the valve from the engine block. I will most likely perform this maintenance at a later date.
After bolting everything back together and reconnecting the negative terminal on the battery, I started the car. Everything seems normal, the engine runs smoother, and no CEL lights turned on. Maintenance successful!
Oh, I also checked the oil and it was a little low so I topped it off.
