| Condition | Possible Cause | Action |
|---|---|---|
|
Hard starting (Engine cranks OK)
|
Faulty spark plug
|
|
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Leaky high-tension cord
|
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Loose connection or disconnection of high tension cords or lead wires
|
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Faulty ignition coil
|
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Dirty or clogged fuel hose or pipe
|
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|
Malfunctioning fuel pump
|
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|
Air inhaling from intake manifold gasket or throttle body gasket
|
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|
Faulty idle air control system
|
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Faulty ECT sensor or MAF sensor
|
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|
Faulty ECM
|
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|
Low compression
|
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|
Poor spark plug tightening or faulty gasket
|
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|
Compression leak from valve seat
|
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|
Sticky valve stem
|
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|
Weak or damaged valve springs
|
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|
Compression leak at cylinder head gasket
|
||
|
Sticking or damaged piston ring
|
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|
Worn piston, ring or cylinder
|
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|
Malfunctioning PCV valve
|
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|
Camshaft position control (VVT) system out of order
|
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|
Faulty EGR system
|