It is vital to change the spark plugs on her Chevrolet Trailblazer every 20,000 or 30,000 mile to keep engine performance and fuel economy. However, if you largely drive your Trailblazer on dirt roads, at short speeds and idle the engine for expanded periods, that is a an excellent idea to check the spark plugs and the rest of the ignition system sooner. Here"s exactly how to remove and also install a new set the spark plugs properly as component of your vehicle"s booked maintenance.

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Remove the Spark Plugs

Remove the air cleaner assembly from the peak of the engine come gain access to all the spark plug wires, if necessary. Pull out the very first spark plug cable by twisting and also pulling the cable boot. If you have actually a Trailblazer v a 4.2L engine, unplug the ignition coil electric connector and unbolt the coil mounting bolt; then pull the ignition coil from the cylinder head. Job-related with one spark plug in ~ a time to stop mixing the wires or coils.

Clean the base roughly the spark plug the dirt and also debris, if necessary. Use compressed waiting or a bicycle wait pump. This will store contaminants native entering the combustion chamber when you remove the spark plugs. Now unscrew the spark plug indigenous the cylinder head making use of a ratchet, ratchet extension and a spark plug socket. If the spark plug appears stuck, spray the basic of the spark plug with penetrating oil or silicone spray adhering to the product"s instructions.


Install the new Spark Plugs

Gap the spark plug utilizing a cable feeler gauge. If necessary, top the automobile Emissions control Information (VECI) brand or your car owner’s hand-operated for the correct space specification for your Trailblazer model. The VECI brand is in the engine compartment top top the height radiator support, firewall or near the strut towers.

Install the spark plug by hand making use of the spark plug socket and ratchet extension. Then tighten the plug utilizing the ratchet, but don"t over-tighten it. Install the spark plug wire, making certain the cable boot snaps in location over the plug terminal. If you have a 4.2L engine model, install the ignition coil over the plug and also tighten the coil mounting bolt; climate plug the coil electrical connector. Remove and install the remainder of the spark plugs following the exact same procedure. Then change the wait cleaner assembly if you had to eliminate it.

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Chevrolet TrailBlazer and GMC Envoy 2002 thru 2006 Haynes fix Manual; Ken Freund and Alan Ahlstrand; 2007 modern-day Automotive Technology; James E. Duffy; 2003

Since 2003 Dan Ferrell has contributed general and also consumer-oriented news come television and the Web. His work has showed up in Texas, brand-new Mexico and also Miami and on assorted websites. Ferrell is a certified automation and control technician from the Advanced an innovation Center in El Paso, Texas.