“Funny Noises”

If your car’s engine starts making a “funny noise,” should you be worried?

It depends on the noise.

Some noises are harbingers of real trouble. Others are usually nothing to worry about. But how do you tell the former from the latter?

Let’s take a look at some examples of both kinds of noises:

Ticking sound when you first start the engine – 

A light ticking sound that goes away within seconds after the engine is first started after it’s been sitting overnight (or longer) is usually no cause for concern . . . provided it’s light and that the sound goes go away within a few seconds, once the engine is running.

What’s happened is all the oil has settled to the very bottom of the engine. It takes a moment for the running engine to build oil pressure. The noise you hear should go away as soon as the system is pressurized.

So, this noise is normal, provided it is very brief  and provided you only hear it at cold-start, when the engine has been sitting for awhile. It is most common on cold mornings, when the car has been left outside all night. The oil is thicker and harder to pump, due to the cold.

If the clattering sounds does not go away a few seconds after start-up – especially if it’s present when the engine is fully warmed up – it could be a more serious problem.

And the first thing you should do is turn the engine off.

The next thing you should do is check oil level. Pull out the dipstick and look at the hashmarks. If it’s low, that could be the cause of the trouble. If it is low – and the noise goes away once the level is topped off – you found the problem and cured it. But remember to find out why it’s low. There is either a leak – look for puddles underneath the car after it’s been sitting overnight – or the engine is burning oil excessively. All engines use some oil, but if there isn’t an underlying mechanical problem – or a leak – it should not be necessary to add more than a quart more often that once every six months. If it is necessary, you might want to try to find out why.

If the oil level is not low, the next thing to check is oil pressure.

If the car has a gauge in the instrument cluster, take a look at it while the engine is idling. Never rev the engine if you suspect mechanical problems, especially lubrication related mechanical problems. The gauge should be reading something above zero. In general, at least 15 pounds – but so long as it’s not nothing.

If it is nothing – if the needle doesn’t move – shut the engine off.

Have the car towed to a shop you trust.  Do not drive it. Do not run the engine at all until the problem is found and fixed. It might just be a bad sending unit; this is what makes the oil pressure gauge – or oil light – work and if the sender is kaput, the gauge may register no oil pressure or the oil light may come on and stay on even though there is oil pressure. But it’s smart policy to assume there isn’t oil pressure if the gauge says there isn’t – or the light comes on and stays on. Worst case, its a false alarm – and $100 for a tow. As opposed to $5,000 for a new engine because the one you had fused into a lump of junk because you ran it with no oil pressure.

Clicking sound as you drive –

This is usually something stuck in one of the car’s tires. It is almost certainly something stuck in one of the car’s tires if the clicking sound gets faster as the car is driven faster and slows down as the car does.

Hopefully, it is something harmless – a pebble in the tread. When you find it, use something not sharp to wedge it out of the tread and the noise should be gone. But you may find a nail in one of the tires. In which case, leave it alone until you can get the car to a tire shop. That noise is annoying but the nail is also plugging the hole it made in the tire. The hole will need to be plugged with something else once the nail is removed – assuming you want  to keep moving.

Squealing and screeching noises –

Several possibilities here, but the most typical are drive belt troubles (loose or misaligned) or accessory troubles such as a problem with the power steering pump caused by low fluid level. Often, the noise will get worse if you rev the engine. Sometimes, the noise is constant. Sometimes, it comes – and goes.

First thing to do is stop the engine, pop the hood and have a look. Check for signs of leaks and seeps around the power steering pump. This accessory is the only accessory that will have a fluid reservoir with a removable cap or dipstick. If you see signs of leakage – and reddish fluid -the usual color of power steering fluid – it’s a clue your problem may be a failing power steering pump. Or failing power steering pump hydraulic lines. If fluid is leaking because of failing lines, the pump will eventually run low, then dry – and it will squeal. Check the fluid level of the reservoir. If it’s low, you’ve likely found your trouble. Topping it off should quiet the squeal . . . until the pump runs low again. You’ll need to have it looked at, but it’s usually not a “right now” thing. Keep spare fluid at the ready for top-offs until you can find time to have the pump (and lines) checked out.

If the power steering pumps seems leak-free and is properly topped off, the next most likely culprit responsible for a case of The Squeals is a loose or misaligned drive belt (or pulley). A quick test that requires no tools is to buy a can of WD-40 aerosol lubricant and – with the engine idling – direct a light spray at the various pulleys and belts (most modern cars have just one serpentine belt that drives all the accessories). If the squeal goes away, you’ve found your problem – and the shot of WD-40 might even  permanently cure it.

If not, it’s time to check the condition and tension of the belt – as well as the condition of the tensioner, which (in cars with serpentine belts) is a thing that looks like a pulley without any accessory attached to it. The tensioner’s job is to maintain the correct . . . tension. If it doesn’t, the belt will squeal in protest – and may even fail or slip off the pulleys, if it’s not tensioned properly.

A squealing belt is more an annoyance than an emergency, but be aware that if a drive belt fails, you will lose the accessory it drove. For example, if the belt which drives the AC compressor fails, you won’t have AC anymore. And if the belt which drives the alternator goes, then you won’t have electricity, soon – once the battery runs out of it. You can drive for awhile, but don’ t drive  longer than it takes to get to a shop or other such where you can deal with this problem. Running the car on battery power will suck the battery dead – and leave you stuck.

If your car has a serpentine belt, you will lose all accessories – including the water pump, without which the car will overheat in minutes.

 A click noise – followed by no noise at all –

This is usually one of two things: Either a bad battery – or a bad connection.  The battery might not have sufficient power to turn the starter motor, which starts the engine.

Or, there’s insufficient voltage – as determined by the car’s computer – to power the fuel injection system and the computer calls a halt to things.

First thing to try is checking the connections at the battery. Feel by hand whether they’re loose; sometimes, jiggling them will result in a “lights on” (and ready to start) condition, like magic. But it’s not magic. You’ve just uncovered a poor connection – and re-established a good connection.

You will probably need to either tighten the cable clamps at the battery terminals, or replace the cables, if the clamps have lost their ability to tightly grip the battery’s terminals It may also be necessary to clean the terminals (and cable clamps). Use a wire brush/terminal cleaning tool for this – which you can buy at any auto parts store for about $10. Once clean, spray the terminals/clamps with WD-40, which will displace any lingering moisture (“WD” stands for water displacement) and also leave a protective coating on the exposed surfaces.

If jiggling the wires – and cleaning the connections at the terminals – doesn’t do anything and the battery is more than three years old, the next most likely culprit for your no-start blues is the battery itself. But don’t chuck it before you test it.

Most auto parts stores (NAPA, Auto Zone, Pep Boys) will do this for free – and if the battery is dead and died prematurely you should be able to get at least some of your money back in the form of a store credit toward your new battery.

Assuming you saved the receipt for your old battery.

. . .

Got a question about cars – or anything else? Click on the “ask Eric” link and send ’em in!