Chapter 20

Troubleshooting Leaks, Squeaks, Smells, and Strange Sensations

In This Chapter

Recognizing the sounds of trouble

Getting rid of squeaks, rattles, and vibrations

Sniffing out unusual smells

Deciphering smoke signals

Locating and dealing with leaks and strange sensations

Troubleshooting directional signals

As you work on your vehicle, you’ll get to know it better. Before long, you’ll become more sensitive to its signals. If something sounds funny or smells funny or just doesn’t feel right, you’ll soon sense it. This can help you forestall expensive repairs because you’ll be able to prevent trouble or deal with it before it becomes a major problem. And if something does need repair, being able to report symptoms accurately will save your mechanic time — and you money.

If you really want to diagnose symptoms professionally, you can buy an electronic diagnostic code reader, or, better yet, a scan tool that plugs into a Diagnostic Communications Link (DCL) mounted under the dashboard of most modern vehicles. Do-it-yourself versions cost from $60 to about $400. They read any trouble codes the on-board diagnostic program (OBD) has recognized and translate the codes into problems you can look up in a repair manual for your vehicle to see what’s involved in buying the part and replacing it yourself.

For those of us who aren’t that ambitious, this chapter shows how to use your eyes, ears, and nose to sense automotive symptoms, and it tells you how to deal with them.

Whenever you encounter a term set in this font, you’ll find it defined in the glossary in Appendix A.

Sounds

You probably know how your vehicle sounds when it’s running properly, and your ears can alert you to anything that sounds strange. Well, tune in to what your ears are telling you! If you hear a strange or different sound, pay attention to it and react accordingly.

If a fan belt or accessory belt “sings” (you hear a high-pitched squeal that stops when you shut off your engine), readjust or replace the belt. These belts should have about 1/2 inch of play and shouldn’t be frayed, cracked, or glazed on the underside. Some belts tend to sing more than others. You can find instructions for adjusting and replacing belts in Chapter 12.

Don’t drive with a broken belt. If you carry a spare belt, you may be able to save yourself towing charges if you know how to replace it. Replacing a serpentine belt at roadside is difficult. You’d need a tow, but at least you wouldn’t be stranded until a new belt could be obtained.

If your radiator “sings” (you hear a continuous high-pitched sound that may continue after the engine’s shut off), check the radiator pressure cap. The rubber gasket may be worn, and steam from the hot engine may be escaping past it. Chapter 12 tells you how to remove a radiator cap safely.

If something ticks rhythmically while your engine idles, shut off the engine, wait ten minutes for the engine to cool down and the oil to settle in the oil pan, and then check the oil level, following directions in Chapter 2. The hydraulic lifters that operate the valves in your engine can make these ticking noises if you’re down as little as a quart of oil. If the level is low, add oil up to the “Full” line on the oil dipstick and check it again in a couple of days. If you have enough oil, have a mechanic check the valve adjustment if your car has adjustable valves (some don’t). Faulty valves can seriously affect your vehicle’s performance and fuel consumption.

If you hear a loud tapping or knocking sound in your engine, pull to the side of the road immediately and call for road service. The source may be just a loose rocker arm or carbon buildup inside the engine, but if it’s a loose bearing or a faulty piston, letting it go unheeded can destroy the whole engine.

Mild knocking or “pinging” may be the result of using fuel with the wrong octane rating. Check your owner’s manual to see whether your vehicle needs low-octane or premium fuel. Most newer vehicles can automatically adjust to a higher or lower octane than they were designed for. But even though you may not hear pinging if you put regular gas in a vehicle that’s supposed to use premium, you probably won’t get the best performance. And putting premium in a vehicle designed for regular fuel only makes the oil company wealthier.

If you hear the engine running after you turn off the ignition, your engine is dieseling. This condition only happens to cars with carburetors. It is usually caused by an idle speed that’s set too high or excessive carbon in the combustion chamber that ignites unburned fuel in the cylinders.

If you hear a whistling noise coming from under the hood, check the hoses for vacuum leaks. If the whistling comes from inside the vehicle, there’s probably a leak in the weatherstripping. Patch the weatherstripping according to the directions in Chapter 24.

If the engine idles with an offbeat rhythm, it isn’t displaying musical talent; it’s probably misfiring, and one of the spark plugs or spark plug wires may be at fault. Try the following:

• With the engine off, check the spark plug cables for breaks or shorts in the wiring.

• With the engine off, remove the spark plugs one at a time and check to see if they’re clean and properly gapped. Replace any that are fouled or burned. Chapter 6 shows you how to do all this spark plug work.

If attending to the spark plugs doesn’t help, have a technician check the ignition system with an electronic engine analyzer. (People used to check spark plugs by holding the end of the spark plug cable close to a metal surface to see whether a spark jumped across when the engine was cranked, but the high voltage in most ignition systems now makes that procedure extremely dangerous.)

If the idling is rough but even, have a technician put your vehicle on an electronic diagnostic machine to check it, or check the compression in each cylinder yourself, following the instructions in Chapter 8. If the engine needs to be rebuilt, you may prefer to get another engine — or another vehicle.

An easy way to determine whether your engine is idling evenly is to place a stiff piece of paper against the end of the tailpipe while the vehicle is idling (with the parking brake on, please). Doing so amplifies the sound and enables you to hear the rhythm. A misfiring cylinder comes through as a pumping or puffing sound. An even but rough idle is a clue that you may need to have your fuel injection system checked out by a mechanic with electronic diagnostic equipment.

If your car sounds like a “Mack truck” or makes some other loud, abnormal sound, a hole in the muffler is probably the cause. Replace it immediately: Traffic cops hate noisy mufflers, and carbon monoxide hates people!

If the horn is stuck, your vehicle is producing what may be the worst noise it can make. Before this happens, have someone honk your horn until you can locate it under your hood. There are usually two horns, and each one has a wire leading to it. If your horn gets stuck, pull these wires to stop the noise (see Figure 20-1) — sometimes you have to pull only one. When you take your car to a service facility to have the horn fixed, tell the mechanic that you pulled the wires, and find out why the horn got stuck. If you can’t get at the horn wires, pull the fuse that goes to the horn to stop the noise. Another way to quiet things down fast is to disconnect one battery terminal. Of course, your vehicle won’t run with the battery terminal disconnected, so this is just a short-term measure until you can fix the horn or help arrives.

If you hear a sound but can’t locate the source, get an old stetho- scope from a medical supply house or your family doctor. As shown in Figure 20-2, take off the rubber disc and insert a piece of tubing in its place (about 1 1/2 inches will do). Then put the plugs in your ears, run the engine, and move the tube end of the stethoscope around the hood area. The stethoscope amplifies the sound as you near the part that’s causing it.

A wooden broomstick works the same way. Place one end on the bone behind your ear and place the other end on the parts that seem to be the source of the noise.

If your tires squeal on curves (and you aren’t speeding), check their inflation pressure, treads, and alignment by using the instructions in Chapter 17.

If you hear whining or humming sounds on curves, your wheel bearings may be wearing. Chapter 15 turns you on to the sensual thrill of repacking them with your bare hands.

Figure 20-1: If your horn gets stuck, pull a wire to silence it.

Figure 20-2: A piece of tubing and an old stethoscope make an efficient troubleshooting device.

If your tires “tramp” (they make a weird, rhythmic sound as you drive), check inflation, tire wear, and wheel balancing (see Chapter 17).

If you hear squealing when you step on the brake, you’ve probably worn the brake pads down too far. Get them replaced immediately. Some disc brakes are naturally noisy, and others have built-in wear sensors that squeal when it’s time to replace the pads. But if the sound gets louder, have the brakes checked or follow the instructions in Chapter 15 and check them yourself.

If you have drum brakes, brake linings that are glazed or worn can cause them to squeal, as well.

If you hear rumbling noises coming from under or toward the rear of the vehicle, the trouble could be a defective exhaust pipe, muffler, or catalytic converter; or it could be coming from a worn universal joint or some other part of the drive train. Have a service facility put the car up on a hoist and find the problem.

If you hear clunking under your vehicle, especially when you go over a bump, check the shock absorbers and suspension system. If the sound is toward the rear, your tailpipe or muffler may be loose.

Squeaks, Rattles, and Vibrations

If you hear suspicious squeaks, rattles, or vibrations, you may be able to save yourself some money by checking and tightening the following items before seeking professional help:

Loose screws and bolts: Check both inside the vehicle and under the hood.

Rearview and side mirrors

Dashboard knobs and trim

Sound-system speaker grills

Window and door cranks and locks

Ashtray and other storage compartments: Are they empty? Do the lids fit snugly?

Glove box: Is the door shut tight? Is anything in the glove box rattling around?

Wheel covers or hubcaps: Remove them and check inside for pebbles.

Outside trim

Trunk: Is something you’ve stashed in there moving around?

If none of these is the culprit, or if the noise persists, have a repair facility find the cause. Often, something inside the vehicle vibrates sympathetically because another part of the vehicle is running roughly.

If your car squeaks like an old taxi, especially when you drive it on a bumpy road, it may just need lubrication. However, the problem may be worn shock absorbers or struts, suspension ball joints, or broken stabilizer links (see Chapter 16).

You may get used to the squeaks and groans, but because they’re caused by parts rubbing together or moving without the proper lubrication, they indicate wear that can damage your vehicle. Obviously, action is required.

Smells

The only odors you should smell inside your vehicle should come from smelly things that you’ve put in it: the takeout lunch that you bought at a drive-through, the perfume that your 6-year-old squirted all over herself, your not-so-freshly groomed dog who’s pressing his nose against your recently washed windows. You can get rid of persistent odors easily by using a spray that eliminates odors rather than masking them. But if you smell any of the items in the following list, take immediate action to correct it:

Do you smell rubber burning under the hood? One of your hoses may have come loose and landed on a hot part of the engine. Rescue it before it melts through.

Do you smell something burning with the hood closed? Feel your wheels. If one is hot, a brake shoe or pad may be dragging, or you may have left the parking brake on. If neither of these checks out, an overheated clutch of a manual transmission car may be the cause.

Do you smell oil burning (a thick, acrid odor)? First check the oil dipstick by following the directions in Chapter 2. Your oil pressure gauge may be lying, and you may be running out of oil. Or your engine may be overheating, and your temperature gauge may be broken. If neither is the case, look around the engine for oil leaking onto the engine block or exhaust manifold. If the oil situation seems to be okay, check the transmission fluid dipstick. Sometimes a faulty vacuum modulator can siphon the fluid out of the transmission and feed it to the engine, where it’s burned. Also, if the transmission fluid is very low, it can be burned in the transmission because the gears aren’t lubricated enough and are getting very hot.

Do you smell oil or exhaust fumes in the passenger compartment? The cause could be burned oil from the engine area, but it also could be a faulty exhaust pipe under the car that lets exhaust gases into the vehicle through the floorboards.

Exhaust fumes contain carbon monoxide, so if you smell oil or exhaust inside the car, be sure to keep your windows open at all times and have the problem checked out as quickly as you can. People have died from inhaling carbon monoxide or from passing out at the wheel because of it. Although the exhaust of most post-1995 vehicles is so clean that a bad headache is probably the worst you can get, have it checked anyway. It never pays to take chances.

Do you smell something sweet and steamy? Take a look at the temperature gauge or light on your dashboard to see whether your engine is overheating. Chapter 12 tells you how to cool things down.

Do you smell rotten eggs? The smell is probably coming from the catalytic converter, which is part of the exhaust system. The converter may be malfunctioning, or you may have a problem with your engine.

Do you smell burned toast (a light, sharp odor)? Unless you’ve brought breakfast with you, it may be an electrical short circuit, or the insulation on a wire may be burning. Check around under the hood. Driving is a bit risky, so either get to the nearest service station or have roadside service come to you.

Do you smell that “new car smell” in your new vehicle? It may be due to toxic emissions from the materials and adhesives used in the passenger compartment. If your vehicle smells strongly of these, until the odor dissipates, consider opening the windows or running the air conditioner while you drive.

Do you smell gasoline? If you just had trouble starting the car, the engine may be flooded. Wait a few minutes and try again. If the smell comes from under the hood, check your fuel injection system or carburetor to make sure that it isn’t leaking fuel. Also check your fuel pump (if it isn’t hidden inside your fuel tank). Leaking gasoline will wash a clean streak across it, which can be seen with the naked eye. Then check all visible fuel lines and hoses that lead to the fuel tank. If they’ve rotted or are disconnected, you’ll smell fuel vapors without seeing any leaks. Taking a look under the vehicle after it has been parked overnight may help, but remember that fuel evaporates quickly, so the clues may be stains rather than wet spots.

Obviously, you shouldn’t smoke while you check for a fuel leak! But then, you never should smoke when you’re working on your vehicle. Gasoline ignites easily, and gasoline vapors can explode, so if you smell gasoline — and you didn’t just fill your tank — find the source of the leak and have it repaired immediately. If your usual repair facility isn’t close by, either drive to the closest garage and have them repair it or call your auto club and have them tow the vehicle to a repair facility.

Smoke

If you see smoke coming from your tailpipe, pay attention to the color for clues to the cause of the problem:

If you see white vapor on a cold morning, disregard it if it stops after the vehicle warms up. If it continues after the engine is warm, a cracked engine block or cylinder head or a leaky head gasket may be letting coolant into the engine. You need professional help with this one.

If you see black smoke and you drive an older vehicle with a carburetor, the fuel/air mixture may need to be adjusted to a leaner setting or the carburetor float may have absorbed gasoline and is flooding the engine.

Black smoke from a vehicle with fuel injection usually requires special diagnosis and should be left to a repair facility.

Check to see whether the fuel/air mixture on either type of vehicle is too rich by running your finger around the inside edge of the tailpipe (first make sure that it’s not hot). If carbon comes off on your finger, the mixture is probably too rich.

If the smoke is light or dark blue, the vehicle is burning oil, which can indicate that oil is leaking into the combustion chambers and you may need to have your valve stem seals replaced or your engine rebuilt or replaced.

If the smoke is light gray, the car may be burning automatic transmission fluid. Check the transmission dipstick following the instructions in Chapter 2. Is the fluid dark and burned-looking? Does it smell burned? If so, changing the fluid may solve your problem.

A faulty transmission vacuum modulator, as found on very old cars, also can suck transmission fluid into the engine, where it’s burned in the cylinders and causes light gray smoke to come out of the tailpipe. Have the mechanic check the problem.

There is hope . . . being low on transmission fluid can cause the same symptoms as a transmission that needs servicing, repair, or replacement. To avoid paying for work that your vehicle may not need, be sure to read Chapter 18 before you opt for major transmission surgery.

Leaks

Pay close attention to leaks. Running a vehicle that’s drastically low on a vital fluid can cause severe damage. After you find the source of the leak, the following information will help you decide whether you can handle it yourself or you need professional help.

If water is getting into your vehicle’s passenger compartment, check the rubber gaskets and weatherstripping around the windows, doors, and sunroof, and refer to Chapter 24 for instructions on how to fix it.

Unless your vehicle has a protective shield under the engine area, here’s an easy way to see whether anything is leaking out from under your vehicle and a few pointers to help you decide what to do about it:

1. Park your vehicle overnight on a clean patch of pavement or a large, clean piece of white paper.

Either tape some sheets of paper together or buy a roll of plain white commercial wrapping paper. Newspaper is too absorbent and can change the color of the stains.

2. Place marks on the paper to show where each of the four wheels is resting, and indicate the front and rear ends of the vehicle.

3. In the morning, move the vehicle and look for small puddles or traces of liquid on the ground or paper. Touch and smell each puddle or trace of liquid.

Here’s how to decipher the evidence:

If it’s clear, watery, and under the air conditioner, it’s probably just normal condensation if you’ve used the air conditioner recently.

If it’s black or dark brown, greasy, and located under the engine area, it’s probably oil. Figure out which part of the vehicle was over the spot: Look under the hood around the oil filter and the engine and under the vehicle for leaks around the oil drain plug, the crankcase, and the oil pan below it.

If it’s thick, black or tan oily liquid, gear oil may be leaking from a manual transmission, the differential, an axle, or the steering gears. Any of these leaks needs immediate attention.

If it’s red, pink, reddish-brown, and greasy and you have an automatic transmission, it’s probably transmission fluid. Check the transmission dipstick (see Chapter 2), and if the level is low, top it off with the proper transmission fluid. Then check the dipstick again in a day or two. If it’s low again, have a professional check the transmission to make sure that the seals are intact.

If it’s watery or slippery; green, red, blue, or yellow; and is coming from under the radiator or engine, it’s probably coolant. To check the radiator, pressure cap, engine, and hoses for leaks, turn to Chapter 12.

Coolant is toxic to children and animals, so leaks need to be remedied quickly. If you can’t locate the source of the leak or your vehicle is losing coolant on a regular basis, consult a mechanic.

If it’s oily; pink, red, or clear; and you find it toward the front bumper (usually on the driver’s side), it’s probably power-steering fluid. The power-steering system is sealed and shouldn’t lose fluid. Chapter 2 tells you how to check the dipstick. If the level is low, add more and check again in a couple of days. If it’s low again, have a mechanic check things out. The good news is that electronic power steering systems eliminate the need for fluid entirely; Chapter 16 describes them.

If it’s a light-colored or clear fluid, it may be brake fluid. Even if the leaks have dried, the stains should be visible. Depending on which part of the car was parked over the puddle or spot, check for brake fluid leaks around the master cylinder and around the brake lines. If the leak is where a wheel was standing, check down the inside surface of that wheel. If you find stains or wetness there, the brake cylinder could be leaking — or a dog could have “marked” your tires!

Leaky brakes are too dangerous to leave unattended. Have a professional repair any brake fluid leaks immediately.

If it smells like rotten eggs, it’s battery acid. Avoid getting it on your hands or clothes and have the battery replaced.

If it smells like gasoline, it probably is! (If you drive a diesel, get to know what diesel fuel smells like so you can identify it.) If the smell is coming from under the hood, check around the fuel pump and the fuel injectors — or the carburetor if your vehicle still has one. If the leak seems to be under the center of the vehicle, check the fuel lines. If it’s under the rear end, check the fuel tank. (Don’t smoke while you do this!)

Gasoline ignites easily, and gasoline vapors can explode, so if you smell gasoline — and you haven’t just filled your tank — find the source of the leak and have it repaired immediately. If your usual repair facility isn’t close by, either drive to the closest service station and have them repair it, or call your auto club and have them either fix it on the spot or tow the car to a repair facility.

If you can’t locate the source of the leak and your vehicle is losing liquid from the radiator on a regular basis, Chapter 12 can help you find the leak and check your radiator pressure cap.

Strange Sensations

This is a catchall category for those things that just “feel funny.” Use the process of elimination to check anything that may cause your vehicle to run roughly: hoses, tires, brakes, oil levels, spark plug connections, the cooling system, clutch, gearshift, and steering linkage. (The book’s index can steer you toward the chapters that include instructions for checking these things.)

Here are a few specific sensations that you may encounter:

If steering is difficult and you have power steering, see “Check the power-steering fluid” in Chapter 2 for information about checking the power-steering dipstick. If it’s low again soon after you fill it, check for leaks in the hoses leading from the unit to the front wheels.

If your car starts wandering instead of running in a straight line, the cause may be worn steering components or wheels that are out of alignment. If the vehicle starts pulling to the left or right, one of the tires may be underinflated or faulty, or the front end may be out of alignment. Look for the solutions to these problems in Chapter 16.

If your car pulls to one side when you step on the brake pedal, Chapter 15 tells you how to check your brakes.

If your vehicle vibrates at highway speeds, the wheels may need to be balanced.

If the engine speeds up but your vehicle doesn’t accelerate when you step on the gas pedal; if there’s a delayed response (or none at all) when you shift gears; or if shifting suddenly becomes awkward or noisy, check the transmission (see Chapter 18). If you have an automatic transmission, you may just be low on transmission fluid, or you may have a disconnected hose or plugged filter.

If you seek professional help, make sure that they check the problems that are cheapest to remedy before deciding that you need major transmission work!

If you notice anything strange when your vehicle’s running, I strongly suggest that you do the under-the-hood check in Chapter 2. This easy, 15-minute monthly checkup can prevent 70 percent of the problems that could cause your vehicle to break down on the highway. By checking for symptoms of trouble in advance, you can save yourself time and money that otherwise would go to towing and repairs.

Directional Signals

Directional signals are vitally important for communicating your intentions to other drivers. If the signals malfunction, they should be fixed immediately — hand signals just don’t do the job. Here’s what to do in a variety of situations:

If all your directional signal lights don’t go on, check the fuse. Chapter 6 has instructions for finding your fuse box and replacing fuses.

If all your directional signal lights go on but don’t blink, your flasher unit is bad. This unit usually plugs directly into the fuse box, so look for trouble there first. After you replace the bulb or fuse that’s defective, the dashboard flashers go back to normal. Isn’t that lovely?

If both signal lights on one side don’t go on, check to see whether the bulbs need replacing. If they don’t, the signals may not be grounded properly. Your mechanic can tell you whether this is the case.

If there’s no light on your dashboard when you move your directional signal lever, either the bulb on your dashboard flasher is out or the unit is malfunctioning.

If one signal light is flashing faster or slower than the others, check to see whether the bulb is the proper one for your vehicle. A heavy-duty bulb will flash faster than a standard bulb. Also check for loose connections or corrosion around the socket the bulb fits into.

Be sure to replace burned-out bulbs at once. They usually cost very little, and changing them involves little labor. Headlights are more expensive because they have to be replaced as a unit (see Chapter 6 for instructions).