Get Yourself Some Automotive Diagnostic Tools


There’s no reason to leave all the more sophisticated diagnostics to your local mechanic. You can purchase your own automotive diagnostic tools and have the same edge in detecting problems as the pros do. These tools will enhance any home mechanic’s diagnostic ability. Here are a few tools and tool types to consider:

Cylinder Compression Gauges
Compression gauges allow a vehicle owner to check the compression in the cylinders. This can demonstrate a number of things about the “engine health” of the vehicle. Bad compression can signify problems such as faulty exhaust valves or head gasket issues. These compression gauges generally fit into the spark plug hole and have a hose and gauge that tells gives a pressure readout. Be sure to follow manufacturer’s instructions concerning how to perform an engine compression test accurately and safely.

Spark Plug Fuel Analyzer
These devices plug into spark plug holes and help to determine information about the gas air mixture in carbureted vehicles.

Timing Lights
Timing lights are often not necessary with today’s on board diagnostics. But there are still some occasions where a hand held timing light might be necessary, such as when you take apart a distributor. Timing lights are not expensive – you can pick one up for around 25 to 30 dollars.

Battery Testers

A battery tester delivers information about the battery such as cold cranking amps, starter and charging system output, and amp-hour delivery. Many of these are combined units that serve several functions at once. There is a large range in price between battery testers depending on what functions they perform. They can be as cheap as 5 dollars or as high as 150.

Circuit Testers and Short Circuit Finders
These also range widely in price and elaborateness. They often attach to electrical contacts or fuse posts and light up when charge or shorts are detected. Simple voltage testers typically cost under 5 dollars. A decent combined s voltage tester/circuit tracer/ short circuit finder might run as high as 150 dollars.


Multimeters are general multipurpose electrical testing devices that usually test amperage (current) voltage (potential) and ohms (resistance). These can be used for testing various electrical devices both in your vehicle and around the house.

Electric OBD Scanners
OBD stands for On Board Diagnostics. There are scanners that allow the home auto mechanic to read the engine’s diagnostic system and even to cancel out codes that are no longer needed.

Gas Analyzers
Gas analyzers read the emissions from a vehicle’s exhaust system to determine various engine issues. They are often capable of measuring CO, HC, O2, and CO2 levels. These units are generally quite expensive, even though they are small, hand held sized items. Some even range into the thousands of dollars.

Antifreeze Testers
These devices test propylene glycol and ethylene glycol antifreeze for cooling efficiency. They are not very expensive – they run around 15 dollars. They can be valuable for showing you whether you have the right water antifreeze mixture in your engine or if your coolant is losing efficiency and may need to be changed.

Ignition Spark Testers

This device is usually placed in line between the spark plug and spark plug wire. It shows the condition of the ignition at each cylinder. It usually uses a flash of light to reproduce visually the intensity of the ignition spark. This can be helpful for demonstrating whether there is an actual ignition problem or a fuel delivery problem. These items are often quite inexpensive selling for around 5 dollars.

These are only a few of the interesting diagnostic tools available to any car owner. They are all reasonably easy to use. With a little practice using them and making conclusions from the information they provide, even an amateur mechanic can move to a higher level of diagnostic skill. Information is always a bonus. Even if at first a car owner is not skilled at integrating some particular information these devices provide into a diagnosis, with repeated use they will make the appropriate connections and become much better at spotting potential problems. In general they will get a better overall sense of their vehicle’s condition. Users should always make sure to follow manufacturer’s instructions for safety and proper use.

Comments are closed.