CONDITION |
POSSIBLE CAUSES |
CORRECTION |
ENGINE WILL NOT CRANK |
- Weak or dead battery
- Corroded or loose battery
connections
- Faulty starter or related circuit(s)
- Siezed accessory drive
component
- Engine internal mechanical
failure or hydro-static lock
|
- Charge/Replace Battery. Refer to
Group 8A, Battery, for correct
procedures. Check charging system.
Refer to Group 8C, Charging
Systems, for correct procedures.
- Clean/tighten suspect battery/
starter connections
- Check starting system. Refer to
Group 8B, Starting Systems, for
correct diagnostics/procedures
- Remove accessory drive belt and
attempt to start engine. If engine
starts, repair/replace siezed
component.
- Refer to Group 9, Engine, for
correct diagnostics/procedures
|
ENGINE CRANKS BUT WILL NOT
START |
- No spark
- No fuel
- Low or no engine compression
|
- Check for spark. Refer to Group
8D, Ignition System, for correct
procedures.
- Perform fuel pressure test, and if
necessary, inspect fuel injector(s)
and driver circuits. Refer to Group
14, Fuel System, for correct
procedures.
- Perform cylinder compression
pressure test. Refer to Group 9,
Engine, for correct procedures.
|
ENGINE LOSS OF POWER |
- Worn or burned distributor rotor
- Worn distributor shaft
- Worn or incorrect gapped spark
plugs
- Dirt or water in fuel system
- Faulty fuel pump
- Incorrect valve timing
- Blown cylinder head gasket
- Low compression
- Burned, warped, or pitted valves
- Plugged or restricted exhaust
system
- Faulty ignition cables
- Faulty ignition coil
|
- Install new distributor rotor
- Remove and repair distributor
(Refer to group 8D, Ignition System
- Clean plugs and set gap. (Refer
to group 8D, Ignition System)
- Clean system and replace fuel
filter
- Install new fuel pump
- Correct valve timing
- Install new cylinder head gasket
- Test cylinder compression
- Install/Reface valves as
necessary
- Install new parts as necessary
- Replace any cracked or shorted
cables
- Test and replace, as necessary
(Refer to Group 8D, ignition system)
|
ENGINE STALLS OR ROUGH IDLE |
- Carbon build-up on throttle plate
- Engine idle speed too low
- Worn or incorrectly gapped spark
plugs
- Worn or burned distributor rotor
- Spark plug cables defective or
crossed
- Faulty coil
- Intake manifold vacuum leak
- EGR valve leaking or stuck open
|
- Remove throttle body and
de-carbon. (Refer to Group 14 for
correct procedures)
- Check Idle Air Control circuit.
(Refer to Group 14, Fuel System)
- Replace or clean and re-gap
spark plugs (Refer to group 8D,
Ignition System)
- Install new distributor rotor
- Check for correct firing order or
replace spark plug cables. (Refer to
Group 8D, Ignition System for
correct procedures.)
- Test and replace, if necessary
(Refer to group 8D, Ignition System)
- Inspect intake manifold gasket
and vacuum hoses. Replace if
necessary (Refer to Group 11,
Exhaust System & Intake Manifold)
- Test and replace, if necessary
(Refer to group 25, Emission
Control Systems)
|
ENGINE MISSES ON
ACCELERATION |
- Worn or incorrectly gapped spark
plugs
- Spark plug cables defective or
crossed
- Dirt in fuel system
- Burned, warped or pitted valves
- Faulty coil
|
- Replace spark plugs or clean and
set gap. (Refer to group 8D, Ignition
System)
- Check Idle Air Control circuit.
(Refer to Group 14, Fuel System)
- Clean fuel system
- Install new valves
- Test and replace as necessary
(refer to group 8D, Ignition System)
|