TOP 3 MAZDA REPAIR PROBLEMS

Inspect the clutch pack and the valve body. The clutch plates and/or discs might have been burned, preventing them from properly releasing grip on the gear. The valve body, on the other hand, may be malfunctioning such that it doesn't effectively channel or cut off hydraulic fluid to the appropriate valves.

Check the gear selector mechanism. It sometimes happens that the digital indicator on the instrument panel or on the gear shifter console displays the N position when the transmission is really in the automatic drive (D) or reverse (R) position.

Check the radiator fan. Chances are it's not spinning as fast as it should to cool the radiator. When your car is running fast or in normal speed, the radiator fan freely turns as there's enough air that goes through your ride's front grille to the radiator. This is possible with the fan clutch's viscous coupling, which disengages the fan from being driven by the engine's crankshaft once it senses that there's sufficient cool air going through the radiator and that the engine is still cool or running in normal temperature. So, if your engine overheats during idle or low-speed operation, it means there's something wrong with your fan assembly.

Inspect the fan when the engine is cool. If you turn the blade by hand and it spins over five revolutions, the fan should be replaced.

Install a new catalytic converter if the stock equipment has already accumulated enough miles as specified in your vehicle's service manual.

Check wirings and connectors in the ignition system for loose electrical connections and burnt or peeled wire insulators. Faulty wiring may ruin the ignition timing and reduce combustion efficiency.

Inspect the air intake system, particularly the air cleaner and mass air flow (MAF) sensor. To determine if your filter has accumulated enough dirt, remove it from its housing and gently tap on it. If dirt and debris are already falling off it, then you may need to replace or clean the air filter right away. (Note: Not all air filters are reusable.) Find out how to replace an air filter here (http://www.automd.com/11/how-to-replace-an-air-filter/).

For the MAF sensor inspection, you can scan the computer. However, to be sure, you can uninstall the sensor and check for accumulated dust or debris where the air passes through. If it's already corroded or dirty, replace it immediately. Another way to test it is by connecting it to a voltmeter and blowing air through it. If the needle doesn't fluctuate, it means the sensor is already faulty.

Check the spark plugs. Fouled plugs can misfire and cause unnecessary delay or advance in the spark. Bad ignition timing can ignite the air-fuel mixture either too soon or too late and leave unburned fuel in the exhaust. Properly working spark plugs have gray or tan-colored electrodes. A sooty, glazed, yellowish, oily, and/or damaged electrode mean the spark plug should be replaced.

Check your engine's pistons, rings, and piston bores. If they're not providing enough compression in the combustion chamber, they could also be allowing the crankcase oil to seep into the cylinder. Oil that gets burned with the air and fuel mixture makes your emission sooty. Replace pistons and rings, and resurface piston bores if necessary.