How to Diagnose Problems Felt in Your Car

If your car lacks power while driving, check the fuel system's pressure and the fuel filter. If there is insufficient pressure, your fuel will not reach the engine to keep power up. If the filter is dirty, again, you will not have enough fuel getting to the engine to keep the car running. Check the spark plugs and wires to make sure the firing order is correct and that the plugs are correctly gapped and have not gone bad. Look at the catalytic converter to make sure it is not clogged or gone bad, as this will cause the exhaust to stay in the engine, and will cause a loss of power. Also look at your piston rings to make sure they are not broken or worn down too low. Check on the EGR valve to make sure it is not dirty and clogged, or has gone bad, as this too will cause a lack of power.

If you have no cool air from the air conditioner, check the belts to make sure they are tensioned correctly or if they are missing. Also look at the a/c clutch coil and pressure sensor to make sure they are not missing or damaged. If they are having problems, the coil will not engage the air conditioning clutch, and you will not have air. Now check the refrigerant system to make sure you have sufficient refrigerant. This is the number one problem found with no air. If you are too low, the system will not produce cool air, and if you continue to run the air, it will in turn cause the compressor to shut down forever. Look at the accumulator to make sure that it is not damaged, as well as the expansion valve. These two things will cause you to get no cool air, even if you have refrigerant.

If you have rough idling, you should first check the air and fuel filters to make sure they are not clogged or dirty. Then look at your carburetor float, because if it is not adjusted right, this can cause too little or too much fuel to flow, and in turn causes a jerky idle. Check the air change sensor to make sure it has a good circuit and is working. Also look at your mass air flow sensor to make sure it is not dirty or gone bad. You can buy mass air flow sensor cleaner from your local parts store to take care of this problem.

Diagnosing and fixing your own car can be rewarding, and keeps money in your pocket. If you still have trouble after diagnosing and fixing your car, visit a local parts store to see if they offer free computer diagnostic testing. Many do, and this will tell you what your problem is, based on your computer's memory banks.