Title: TROUBLE SHOOTING A NO START CAR
1 TROUBLE SHOOTING A NO START CAR
2Remember a car must have Spark, Fuel,
Compression and proper Ignition and Valve timing
to run.
3Does 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
4Does 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!
5Crank 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.
6 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.
7Does 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
8Pump 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.
9Noid 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.
10If 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.
11Does 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
12Vacuum 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
13Is 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.
14Valve timing
- Valve timing is also important did the timing
chain or belt jump a tooth. Make sure rotor
turns when engine is cranked.
15Look 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.
16You 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.
17The End
02-28-2001