TROUBLE SHOOTING A NO START CAR

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TROUBLE SHOOTING A NO START CAR
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Remember a car must have Spark, Fuel,
Compression and proper Ignition and Valve timing
to run.
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Does the car have spark?

• Crank engine and check for spark at coil wire
• If no spark check for Battery voltage at coil
• Battery voltage at ignition switch
• if older car check points. Is the gap and Dwell
  OK, are they pitted, what about the condenser.
• If newer car check resistance of pickup coil
• check for a AC signal out of the pickup coil

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Does the car have spark?

• check for a resistor, is it OK
• check for broken wires between ignition switch
  and coil
• does this car have an ignition fuse, a broken
  wire.
• Does the Distributor turn.
• Check the Camshaft Position Sensor
• Check the Crankshaft Position Sensor
• Find out why there is no spark!

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Crank engine and check for spark at plug

• If no spark it must be a
• bad spark plug
• spark plug wire
• Distributor cap
• or rotor if you had spark at the coil.

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If you have spark and it still doesn't start

• did you check for fouled spark plugs.
• Fuel or oiled fouled spark plugs will prevent a
  car from starting.

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Does the Car have Fuel?

• Check fuel tank _ Does the gauge work
• If no gas put some in it.
• You cannot believe how many cars I have had towed
  in on a hook because they were out of gas

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Pump throttle valves (gas pedal) watch for a
stream of gas out of the accelerator nozzle.

• If no gas check for broken lines, plugged fuel
  filter(s) or bad fuel pump.

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Noid Lights

• If car has throttle body injection take off air
  cleaner check for fuel when cranking. If port or
  central fuel injection check for fuel at pressure
  connection with gauge.

• If no gas install noid lite and check for power.

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If car is flooding

• Is the choke to tight, is there dirt in the
  needle and seat, is the float set incorrect or is
  it gas logged.

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Does the engine have good compression?

• Perform a compression test on all cylinders not
  just one or two and assume that the others are
  O.K.
• If bad perform a cylinder leakage test

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Vacuum Leaks

• Vacuum leaks also go along with compression, did
  someone leave off a PCV hose or power brake hose
  or did one just break _ if the air did not go
  through the carburetor there is no gas in it and
  it will not fire.
• Perform a smoke test on the car

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Is the engine timed?

• Ignition timing must be right on. Are the plug
  wires in the right firing order, do they go
  around in the cap in the right direction.
• If DIS are the cables on the right coil
• When 1 piston is at T.D.C. (compression
  stroke) does the timing mark line up and does
  the rotor point to the 1 tower in the
  distributor.

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Valve timing

• Valve timing is also important did the timing
  chain or belt jump a tooth. Make sure rotor
  turns when engine is cranked.

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Look up the information for the specific car you
are working on there are to many cars to remember
the firing order on each car made yesterday and
today.
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You need to use some common sense in trouble
shooting there are some short cuts, but some
times you have to start at square one with the
basics. Techs who skip around and jump from step
to step will take along time to troubleshoot a
car. These are some of my thoughts on how to do
it. Use your thinking skills and come up with a
plan for yourself.
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The End
02-28-2001