Troubleshooting engine problems

Have you got engine problems? Are you sometimes stressed out trying to find out what is going wrong regarding your motor car’s engine? “The car’s engine is basically a converter of energy,” says Oral Baugh, a St Andrew-based auto mechanic. “It converts the energy of heat into the energy of motion.”

According to Baugh, “This conversion begins when you engage the starter.”

While there are thousands of things that can go wrong in your car, under each problem, here is a list of possible causes.

Engine keeps running when ignition is turned off:

• Engine idling too fast (most common cause)

• Overheated engine

• Late ignition timing

• Wrong fuel

• Lean fuel mixture

• Heavy build-up of carbon in combustion chambers

Engine backfires:

• Raw gasolene in exhaust system as a result of flooding due to excessive use of the starter before the engine starts

• Excessive carbon deposits

• Late ignition or valve timing

• Unwanted air leaking into the engine

• Sticking or burned valves

• Cracked distributor cap

• Crossed sparkplug wires

• Loose wires in ignition system

Engine oil warning light comes on or oil gauge reads low:

• Oil leak

• Low oil level

• Malfunctioning oil pump

• Oil heavily contaminated

• Faulty sending unit or wiring

• Engine overheating

• Oil too thin

• Worn crankshaft bearings

• Worn piston rings

• Cracked oil lines inside engine

• Engine oil too light or oil too thin

Engine oil consumption excessive:

• Excessive oil speed driving

• Oil pressure too high

• Engine overheating

• Raw gasolene entering crankcase

• Wrong type of engine oil

Engine oil leak:

• Faulty gaskets

• Seeping oil filter or fuel pump

• Faulty rear main-bearing or timing cover seals

• Defective crankcase-ventilation system

Engine makes rattling noise when idling:

• Worn or loose timing gears or chain

• Loose piston wrist pins

• Loose flywheel or cracked automatic-transmission drive plate

• Loose generator or alternator

• Loose power-steering pump or air-conditioning compressor

• Broken heat-riser valve

• Worn water pump

• Worn motor mounts/loose exhaust system

Engine races on idle:

• Idle-adjusting mechanism improperly adjusted

• Sticky accelerator linkage

• Broken or weak pullback spring

• Sticking pivot on gas pedal

• Unwanted air entering the engine due to such things as worn intake manifold or carburettor gaskets or a disconnected vacuum hose

Engine makes tapping or clicking noise at all speeds:

• Damaged pistons hitting top of cylinder heads

• Broken valve spring

• Loose tappet-adjusting screw

• Worn rocker-arm assemblies and pushrods

• Low oil level or pressure

• Plugged or restricted oil passages to valve mechanism

• Faulty hydraulic lifters

Engine stalls when gas pedal is suddenly released:

• Dashpot defective or improperly set

• Leaking carburettor gaskets

• Disconnected vacuum hose

• Leak at intake manifold

• Engine idling too slowly

• A poorly tuned engine

The engine turns over but will not start:

• A common cause: the engine is flooded with an excessive quantity of gasolene. This can usually be overcome by waiting a few minutes and then pushing the gas pedal just once, all the way down to the floor (pumping the gas pedal up and down several times only worsens the flooding condition), Baugh said. Then, with the gas pedal held down to the floor, engage the starter motor and turn over the engine several times. (Usually, the engine will start.)