Troubleshooting a Car That Won't Start

Troubleshooting a Car That Won't Start

• Did you ever consider those wonderful days when your car won't start? If you left your lights, radio, or some other electrical gizmo on after you parked the car, you know what the trouble is: Your battery is dead. Of course, there are other possible reasons that your car won't start.Won't-start symptoms
• Your car may not start for a number of reasons. The following list outlines the most common circumstances and tells you what action you can take to try to remedy each situation:
• The car is silent when you turn the key in the ignition. Check the battery terminal cable connections. (See How to Check Your Car Battery.) If they look very corroded, force the point of a screwdriver (with an insulated or wooden handle) between the connector and the terminal post and twist it to lodge it firmly. Then try to start the engine. If it starts, you need to clean or replace your cables.
• The car makes a clicking noise but won't start. This sound usually means a dead battery. If not, check the wiring to and from the starter for a loose connection.
• The car cranks over but won't start. Check the fuel supply to your engine. If that's okay, check whether the electrical spark is getting to your spark plugs.
• The engine starts but dies. If your car has a carburetor, check your carburetor adjustment and your choke to see whether the choke is first closing and then opening. If you have fuel injection, you'll need professional help.
• The car won't start on rainy days. Check inside the distributor cap for dampness. If you find moisture
• , get some mechanic's solvent from your friendly service station — they use it to clean car parts — or buy an aerosol can of it at an auto supply store. To evaporate any dampness inside the distributor cap, turn the cap upside down and pour or spray some solvent into it. Swish it around and pour it out. Then dry the cap as best you can with a clean, lint-free rag and replace the cap.

Use only clean solvent; even a tiny speck of dirt can foul the points. Gasoline won't do because a spark can ignite gasoline fumes and cause an explosion or a fire



.The car won't start on cold mornings. For vehicles with carburetors,check the choke. Is it closed? Does it open? If you have fuel injection, you'll need to have a professional diagnose the cold-start problems.The engine misses while idling. Check the points (if your car has a non-electronic distributor) and the spark plugs. (How to Remove Old Spark Plugs explains getting bad spark plugs gone.) Also check the fuel pump, fuel filter, and carburetor, if you have one. (If your fuel filter’s the problem, check out How to Change Your Vehicle’s Fuel Filter.)The engine misses or hesitates during acceleration. Check the accelerator pump in the carburetor (if equipped), the spark plugs, the distributor, and the timing. 



The engine knocks or pings. Check your timing; also check the octane rating of the fuel you're using. The owner's manual can tell you whether your vehicle needs regular unleaded or premium gasoline. Check the cooling system. (which The Essentials of Checking and Maintaining Your Vehicle’s Cooling System explains) Do a compression check on the engine cylinders. (Check out How to Check an Engine’s Cylinder Compression.)Jumping a start 



To safely jump a start, follow these steps:1. Take out your jumper cables.It's a good idea to buy a set of jumper cables and keep them in the trunk compartment. If you don't have jumper cables, you'll have to find a Good Samaritan who not only is willing to assist you but has jumper cables as well.2. Place both cars in Park or Neutral, with their ignitions shut off and their emergency brakes on.3. Remove the caps from both batteries (unless they're sealed).Batteries produce explosive hydrogen gas, and a spark could set it off. If the caps are open, you can avoid such an explosion. (Sealed batteries have safety valves.)4. Connect the cables.

• The positive cable has red clips at either end, and the negative cable has black clips. It's important to attach them in the proper order:1. First, attach one of the red clips to the positive terminal of your battery (it has "POS" or "+" on it, or it's bigger than the negative terminal).2. Attach the other red clip to the positive terminal of the GS's car.3. Attach one of the black clips to the negative terminal on the GS's battery.4. Attach the last black clip to an unpainted metal surface on your car that isn't near the carburetor (if your car has one) or battery

.Figure 1 shows how both the positive and negative cables should be connected.

 

• 5. Try to start your vehicle.If it won't start, make sure that the cables are properly connected and have the GS run his or her engine for five minutes. Then try to start your car again. If it still won't start, your battery may be beyond help.
• 6.
• Disconnect the cables, thank the Good Samaritan, and resume your life.Don't shut off your engine; drive around for a while to recharge your battery.

• Don't shut off your engine; drive around for a while to recharge your battery.
• 
  

  If your alternator light stays on or the gauge on the dashboard continues to point to "Discharge" after your car's been running, make sure that your fan belt is tight enough to run your alternator properly. If your battery keeps going dead, have a professional check both the battery and your alternator.

• 
  

  In any case, never drive around with a light or gauge that reads "Trouble"; have it checked out immediately — that's why those gauges are in there!

• For you experience See also
• 
     

1. How to Diagnose Problems If Your Car Won't Start
2. If your car won’t start and you left your lights on after you turned off the engine, your battery is dead. But your conventionally fueled vehicle may not start for a number of reasons. The following list outlines the most common circumstances and tells you what action you can take to try to remedy each situation:
3. The car is silent when you turn the key in the ignition: Check the battery terminal cable connections. If they look really corroded, you need to clean the battery posts and cable connectors or replace the cables and try to start the engine.
4. The car makes a clicking noise but won’t start: This sound usually means a dead battery. If not, check the wiring to and from the starter for a loose connection.
5. The engine cranks over but won’t start: You may be out of fuel, or the fuel isn’t getting to your engine. If it’s not a fuel problem, the electrical spark isn’t getting through to the spark plugs.
6. The engine starts but dies: If you have fuel injection, you need professional help.
7. The car won’t start on rainy days: If you have a non-electronic ignition system or an electronic ignition with a distributor cap, check inside the cap for dampness.
8. Be sure the ignition is off and the vehicle is in Neutral or Park before you raise the hood and remove the distributor cap.
9. If you find moisture, get some mechanic’s solvent f rom your friendly service station — they use it to clean car parts — or buy an aerosol can of it at an auto supply store. To evaporate any dampness inside the distributor cap, turn the cap upside down and pour or spray some solvent into it. Swish it around and pour it out. Then dry the cap as best you can with a clean, lint-free rag, and replace the cap.
10. Use only clean solvent; even a tiny speck of dirt can foul the points. Gasoline won’t do because a spark can ignite gasoline fumes and cause an explosion or a fire.
11. The car won’t start on cold mornings:  If you have fuel injection, you need to have a professional diagnose the cold-start problems.

Engine Fails to Fire Up
Corroded or loose battery cables can interfere with your starting system.

Always start with the obvious. Make sure you have fuel in the tank; maybe the fuel gauge has stopped working. After that, turn on the headlights. They should be bright, a quick and easy way to check for battery power.

Then check for faulty components in the fuel and ignition systems. If you have not changed it in the past 12 months or so, the fuel filter might be clogged, obstructing the flow of gas; after years of service, the fuel pump might have failed as well. Examine the ignition system; look for broken, loose or disconnected spark plug wires or a failed ignition coil.

Check the timing chain. A worn-out or defective chain will fail to synchronize cylinders and valves, making the engine unable to operate. Finally, check cylinder compression.

Engine Fails to Start When Cold
Faulty spark plugs will fail to ignite the air/fuel mixture in the combustion chamber.

If your engine seems to give you trouble only when cold, there are some specific components to look at. Using a voltmeter, check for battery power. Make sure fuel is reaching the injections and the fuel filter is not clogged. Also, check the condition and gap of the spark plugs--clean and recalibrate the plugs if necessary. Then troubleshoot the engine coolant temperature sensor and engine control system.

Engine Fails to Start When Hot

If the starting system only gives you trouble when the engine is hot. check the fuel filter and make sure the fuel injection system is receiving fuel. In rare cases, the fuel system may be experiencing vapor lock. This is caused by engine heat transferring to the fuel and creating bubbles. You will notice the engine stalls, lacks power or it is hard to start or does not start at all. Inspect the feed and return lines and see if any are touching a hot engine part.

Starter Motor Operates

Sometimes, the starter motor will operate but the engine will not turn. The problem might be in the starter motor itself. The most common problem is a worn or broken starter pinion or drive plate. Remove the motor for inspection.

Maybe the starter motor itself does not turn. Check that the battery terminals are tight and clean. Then check the battery charge. When attempting to start the engine, make sure the transmission is in Park (P) or Neutral (N). Also, check the starting circuit for broken, loose or disconnected wires and cables from the battery to the starter solenoid, the ignition switch and the starter motor.

Next, check components in the starting system like solenoid, ignition switch and starter motor. It is possible the pinion on the motor is jammed. Remove the starter motor. Finally, check the Transmission Range (TR) sensor. The sensor may need adjustment or replacement.