A variety of sounds can come from under the hood, some of which are listed below. Keep a list with you in your glove box so you can reference them:

Ticking – Typically, low oil can result in a constant tick, tick, tick in rapid succession – Location: This noise is normally on the top of the engine unless your engine is a V-6 or V8 in which case, on front-wheel drive vehicles, it would be front or back of the engine. Trucks and rear-drive cars with V-type engines would have the noise on the left and right sides. Diagnosis & Prognosis: Check oil level and replace what is lost, if it is low. If it persists, consult your service professional. The actual ticking sound is from a lack of lubricant at the lifter/valve stem, rocker arm, push-rods (if equipped) and camshaft causing a slight delay in the spring return or the actual pushing movement resulting in a slight gap in the contact of a few of these components causing them to tap (or tick) against each other. Other sources of “tick”: Normal operation of A/C compressor (occasional tick or clack); Debris in electric fan, clear debris with engine and fan off (allow to cool prior to cleaning); Exhaust leak at engine, seek professional help but you are OK to drive.

Squealing – Engine belts are considered a wear item. This is because they are attached to moving components (pulleys) and suffer a fair amount of friction over time. They also dry out and crack under heavy use or being left to the elements, particularly in dry states like Arizona. Location: Passenger side of engine compartment on FWD cars and Front of engine compartment on RWD cars and trucks. Diagnosis & Prognosis: Harder to pin-point to a small point with a makeshift megaphone. Shut off car and look to see if there are indeed cracks on the belt(s)…you can check by depressing the belt and looking for cracks as it flexes. If you can see cracks with or without this action then you should plan for a replacement immediately. Once confirmed, make an appointment with your service professional. An unusually dry belt can squeal for no other reason, for this you can buy a spray can of Belt Dressing to mitigate the noise. It helps to condition the belt for better grip. Other sources of a squeal: Or squelching would be low power steering pump fluid level, check and fill as needed, PS pumps can fail and cause a great deal of squelching. Seek a professional if you believe this is the cause; Water pumps have a bearing that can get worn and squeal, seek a professional; Idler pulley or wheel bearing, seek professional.

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