Diagnosing Minor Problems

Cooling System Problems

Cooling system problems are usually indicated by an overheating engine, a loose fan belt, slow engine warm-up or less often, an engine running too cold.

Checking an Overheating Engine

Do not open up a hot cooling system. Turn off the engine and wait for the system to cool.  A good rule of thumb is to touch the outside of the radiator when you think it's cool enough.  If it's too hot to touch, it's too hot to open.

After the system has cooled, check the coolant level.  If it is low, fill the radiator or coolant recovery system  to the appropriate levels as indicated in the section, "Cooling System Function."

Turn the ignition on and check for leaks.  Check for leaks again after the system has warmed up and pressure has built.  With the engine running, check the coolant circulation by feeling the upper and lower radiator hoses.

CAUTION:            Keep your hands away from moving parts.

If the upper hose is cooler, circulation is restricted and could mean that the thermostat did not open.  In this case, take your car to a professional cooling system specialist.

Adjusting a Loose Belt

A slipping fan belt may cause your engine to overheat.  A sign of a slipping belt is a high-pitched squeal during acceleration.  Check to see if the belt is loose on the pulley.  To adjust it, loosen the retaining bolts with an appropriate sized socket wrench as illustrated.  With a wooden hammer handle, carefully apply leverage to move the accessory (usually the alternator) slightly to tighten the belt.

CAUTION:   Never pry against thin-walled areas of the accessory.

Partially tighten the bolts and check the belt tension.  Once the tension is correct, tighten the bolts securely.

Start the engine and let it idle.  Observe the belt in the pulleys.  The belt should not ride higher than 1/16 of an inch above the top of the pulley groove.  If it does, you have the wrong-sized belt, and you should replace it.

If after checking both the cooling system and the belts, you are still having problems with overheating, see a cooling system specialist.

Battery Problems

A major cause of undercharged batteries is a loose alternator belt.  After the battery provides the energy to start your vehicle, the alternator takes over to produce the electricity to run the car's electrical accessories, plus recharge the battery.

The regulator monitors the current flowing from the alternator to the accessories and the battery.  If the alternator belt is loose, it will slip and reduce alternator output.  Then, when the lights, radio and other electrical accessories are on, the alternator will not be able to run all of them and still recharge the battery.

We have already discussed how to tighten a loose belt.  In fact, in many automobiles, the same belt is used for the fan and the alternator.  If you need to tighten your alternator belt, reread the section entitled,

"Adjusting a Loose Belt".

Engine Will Not Crank

The majority of failure-to-start problems are caused by corroded terminals, low electrolyte level, or a loose alternator belt.



Things to Check

Turn on the headlights and then try to start the engine.  Observe the headlights.  If they dim considerably, check for corroded and loose battery cables.  If the cables are corroded, clean them.  If they are loose, tighten them.  If the cables are not corroded or loose, the battery is discharged.  Recharge it and try this test again.  If the headlights do not dim at all, this is a good indication of a starter problem.

Brake System Problems

If the brake pedal feels spongy or soft when you step on it, it is an indication of air in the brake hydraulic system, or other serious brake problems.  Have the brake system professionally checked as soon as possible.

Emergency Brake Safety Check

Whether your emergency brake is a hand or foot lever, it should click from five to nine times when pulled or depressed.  If it does not, consult a mechanic specializing in brake work.

Power Steering Problems

Power steering systems seldom break down completely.  If there is a problem, you will notice a noise, a leak or a handling problem.

To diagnosis and correct any problems you may have with your vehicle's power steering system, follow the checklist given.

CAUTION:            The power steering system operates at extremely high pressures.  Do not open the system or check the belts while the car is running.

  1. Check the fluid in the power steering pump.  If the level is low, add power steering fluid.
  2. Start the engine and turn the steering wheel easily to the extreme left or right position to remove air trapped in the system by the added fluid.  Do not force or hold the wheel to the extreme left or right.  This causes unnecessary pressure in the system.  Any squeal or hum you hear while the steering wheel is in the extreme positions is usually normal.
  3. With the engine off, check the reservoir again.  You may need to add more fluid if the system was low.  If so, repeat step 2. 
  4. Check for proper tension in the power steering belts.
  5. Check the tire pressure, low tire pressure creates an additional demand on power steering.

Automatic Transmission Problems

The first indication of transmission trouble is more noticeable when the transmission is cold and you shift into gear for the first time.  Indications of problems will be:

  1. Delay going into gear.  The delay usually lasts for four or five seconds.
  2. Harsh up and down shifts.

Check fluid level with the engine at normal operating temperature.  If the fluid level is low, add the recommended type of fluid to the proper level while the engine is running.

Transmission fluid color is normally red or orange which indicates the fluid is in satisfactory condition.  Fluid that is discolored or has a burned smell indicates the need for transmission service.