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Q: Truck not passing emissions test

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My truck did not pass an emissions test, and a full tuneup was recommended. It's a V6.

A: For a vehicle that is over twenty years old...

For a vehicle that is over twenty years old, a full tuneup could mean a lot of maintenance, from plug, wires, filters and injectors, to major components, in order to fix the emission failure. These engines have a problem with the injection system that can cause the system to run too rich, or too lean. I recommend having a mechanic, such as one from YourMechanic, run a thorough diagnostic check to see what the engine would need to pass the test, and put together a repair list.

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