Chevy Engine Troubleshootingby Dan Ferrell
Your Chevy engine is not much different from many other makes and models you see on the road. An internal combustion engine needs the proper air-fuel ratio, burned by a healthy spark and delivered at the right time. A good and strong explosion will efficiently turn your crankshaft to provide the torque and speed power. Several systems help the engine accomplish these tasks, and that's where your ability to troubleshoot will be useful. Which component in which system is causing trouble?
Check your battery, ignition system and starter if your Chevy engine refuses to start. A weak battery or spark will not provide the electrical power to turn your starter or fire the air-fuel mixture. Check for corroded battery connections, worn spark plug wires and plugs, faulty coil and ignition control module. Also, make sure your starter and fuel pump are working properly.
Check your vacuum system if the engine stalls or runs rough on idle. A leaking vacuum hose or intake manifold gasket will lower internal pressure, affecting air-fuel delivery. Make sure your fuel pump has the correct pressure, there is no air intake restriction--clogged air filter--and the ignition system is providing a good spark.
Check the ignition coil first if the engine loses power. A worn or faulty coil will not deliver a strong spark. Also inspect ignition timing and the fuel pump. If you just replaced the spark plugs, make sure their gap is correct; then check for a blown cylinder gasket, low compression or restricted exhaust system.
Check your ignition coil if the engine misses when you accelerate. The coil may be providing an intermittent spark, making some of the cylinders miss combustion; then look over the distributor and rotor for damage, spark plug wires and plugs for wear.
Check your fuel system and alternator if you hear knocking engine noises every time you accelerate or drive up a hill. Also inspect the ignition system, including spark plugs and distributor components and possible small vacuum leaks--a loose or torn vacuum hose.
- A hand-held electronic scanner will greatly help you identify hard-to-diagnose engine problems. The scanner communicates with the engine's computer to retrieve stored trouble codes produced by specific systems and faulty sensors that may be affecting engine operation. You can buy one at most auto parts stores. Consult your service manual to locate and identify components if necessary. You can buy a service manual at most auto parts stores or consult one for free at your local public libraries.
Items you will need
- Photo courtesy of Rich Niewiroski Jr. at Commons Wikimedia.org.