List of 19 Major Car Engine Problems and Their Possible Causes

In this article, you’ll learn what the different Car Engine Problems and Their Possible Causes are. If you found this helpful, please let us know in the comments.

Car Engine Problems

This post deals with various engine troubles and their causes. The remedies to these troubles are not given because they are self-understood according to the causes. Some of the major troubles of scooters, cars, and tractors are also elaborated with their causes.

List of Car Engine Problems

Following are the major car engine problems:

#1 Engine does not turn over when starting is attempted

• Discharged battery
• Open starting circuit
• Jammed Bendix drive
• Jammed cranking drive
• Jammed engine
• Also, causes are listed under item 3

#2 Engine turns over slowly but does not start

• Discharged battery
• Defective cranking motor
• Bad connection in starting circuit
• Undersized battery cables
• Also, causes listed under item 3

#3 Engine turns over at normal speed but does not start

• Defective battery system
• Defective or over-chocking fuel system
• Air leakage in the intake manifold or carburetor
• Defective engine

#4 Engine runs but misses one cylinder

• Defective spark plug
• Defective distributor lead or cap
• Stuck valve
• Defective piston or rings
• Defective head gasket

#5 Engine runs but misses different cylinders

• Defective ignition
• Defective fuel system
• Loss of compression
• Defective valve action
• Defective rings
• Overheated engine
• Sticking manifold heat control valve
• Clogged exhaust

#6 Engine lacks power acceleration

• Defective ignition
• Defective fuel system
• Clogged exhaust
• Throttle valve not opening fully
• Loss of compression
• Excessive carbon in the engine
• Defective valve action
• Excessive rolling resistance from low-type pressure, dragging brakes, wheel misalignment, etc.
• Heavy oil
• Wrong or bad fuel

#7 Engine lacks power or high-speed performance, hot only

• Engine overheats
• Defective choke
• Sticking manifold heat control valve
• Vapour lock

#8 Engine lacks power or high-speed performance, cold only

• Stuck automatic choke
• Due to a stuck manifold heat control valve
• Stuck cooling system thermostat
• Stuck engine valves

#9 Engine overheats

• Lack of water
• Late ignition timing
• The loose or broken fan belt
• Defective thermostat
• Clogged water jackets
• Defective radiator hose
• Defective water pump
• Insufficient engine oil
• High-altitude, hot climate operation
• Late valve timing

#10 Rough idle

• Incorrect carburetor idle adjustment
• Malfunctioning crankcase ventilator valve on closed crankcase ventilating system
• Also, causes listed under items 6, 7 and 8

#11 Engine stalls cold or as it warms up

• Closed choke valve
• Fuel not getting to or through the carburetor
• The manifold heat-control valve stuck
• Engine overheats
• Too low setting of idling speed

#12 Engine stalls after idling or speed driving slow

• Defective fuel pump
• Overheating
• High carburetor float level
• Incorrect idling adjustment

#13 Engine stalls after high-speed driving

• Vapor lock
• Defective carburetor ventilating or idle compensator valve
• Engine overheats

#14 Engine backfires

• Ignition timing off
• The spark plug of the wrong heat range
• Excessive rich or lean mixture
• Overheating of the engine
• Carbon in engine
• Valves hot or sticking

#15 Smoky exhaust (Blue smoke & Black smoke)

• Excessive oil consumption
• Excessive rich mixture

#16 Excessive oil consumption

• External leaks
• Burning oil in the combustion chamber

#17 Low oil pressure

• Worn engine bearing
• Engine overheating
• Oil dilution or foaming
• Defective lubrication system

#18 Excessive fuel consumption

• Nervous driver
• High speed
• Short-run operation
• Excessive fuel pump pressure or pump leakage
• Choke partly closed after warn-up
• Clogged air cleaner
• High carburetor float level
• Stuck or dirty float needle value.
• Worn carburetor jet
• Stuck metering rod or full power piston.
• Idle too rich or too fast
• Stuck accelerator-pump check value
• Carburetor leaks
• Faulty ignition
• Loss of engine compression
• Defective value action
• Clutch slippage
• Excessive rolling resistance from low pressure, Dragging brakes, wheel misalignment, etc.

#19 Engine is noisy

• Value and tappet noise
• Spark knock due to low octane fuel carbon advance ignition timing. Also, causes listed under item 14
• Worn connecting rod bearing or crankpin, misaligned rod, lack of oil
• Worn or loose piston pin or lack of oil
• Worn rings, cylinder walls, low ring tension, broken rings
• Piston slap due to worn pistons, walls, collapsed piston skirts, excessive clearance, lack of oil, and misaligned connecting rods.
• Regular noise, worn main bearings, irregular, worn end thrust bearings.
• Rattles, etc., from loosely mounted accessories, generator horn, oil pan, etc.

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Conclusion

That’s it, thanks for reading. If you have any questions about “Car Engine Problems,” ask in the comments, I’ll respond to you. If you like this article, then please share it with your friends.

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