Starter: What appears to be a defective starter actually may be a dead battery or poor connection. Ask the mechanic to check all connections and test the battery before repairing the starter.

Alternator: Loose wiring can make your alternator appear defective. It should be checked for loose connections and perform an output test before replacing the alternator.

Battery: Corroded or loose battery terminals can make the battery appear dead or defective. The terminals need to be cleaned and the battery needs to be tested battery function before replacing the battery.

Muffler: A loud rumbling noise under your vehicle indicates a need for a new muffler or exhaust pipe.

Tuneup: The old-fashioned "tuneup" may not be relevant to your vehicle. Fewer parts, other than belts, spark plugs, hoses and filters, need to be replaced on newer vehicles. Follow the recommendations in your owner's manual.