1. Check the fluids and do a maintenance check of your car. To do this, check the oil, transmission fluid, and coolant fluid levels in your car. If the levels look fine, move on to the maintenance check. This is where you would spot check your engine for frayed belts, leaking fluids or anything unusual that stands out to you. If you find an abnormality during the check, fix that first and see if your car problem ceases.
Listen for new and strange noises your car is making. A knocking sound in the engine is serious and needs immediate attention, whereas a whining sound may be a belt, which is less serious.
Take note of any strange smells. A chemical-like smell signifies an electrical problem. A strong exhaust odor could be a gasket leak or exhaust problem.
Look over your vehicle and take note of anything unusual. If you choose to, take your vehicle into a local car parts shop. Most of these places offer to do a free code read of your engine, and may be able to pinpoint any problems. A code readeris where the technician can plug a diagnostic tool into your car's diagnostic port, usually located in the driver's side lower dash. The tool detects problems in your car and diagnoses the problem for you.
4. Take your car into a shop, if all else fails. Tell the mechanic anything you found while trying to diagnose the problem yourself.
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