Suzuki: Engine K6A-YH6. Manual - part 11

5-8

TESTS AND ADJUSTMENTS

5

Figure 5-17

7.

After completing the inspection, remove the special 
tools. Wrap teflon tape (4) on the oil pressure 
sending unit (5) threads and tighten it to 
specification.

Oil Pressure Sending Unit Torque: 115 lb-in. 
(13 N·m)

8.

Start the engine and check oil pressure switch for 
leaks.

TN0355

5

4

6-2

DIAGNOSTIC TROUBLESHOOTING

6

Troubleshooting

 Condition

Probable Cause

Remedy

Engine starts hard (but cranks properly).

Fouled spark plug(s).

 Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty fuel injector.

Check fuel injectors. (See “Injectors” on 

page 7-9.)

Throttle body gasket leaking air.

Check throttle body and gasket. (See 

“Throttle Body” on page 7-4.)

Faulty ISC (idle speed control) valve.

Check ISC (idle speed control) valve. (See 

“ISC (Idle Speed Control) Valve” on 
page 7-3.)

Faulty throttle position sensor.

Check throttle position sensor. (See 

“Throttle Position Sensor” on page 7-3.)

Faulty manifold pressure sensor.

Check pressure sensor.(See “Pressure 

Sensor” on page 7-3.)

Intake manifold leaking air.

Check intake manifold and gasket. (See 

“Intake Manifold” on page 7-4.)

Exhaust restriction.

Check exhaust manifold. (See “Exhaust 

Manifold” on page 7-7.)

Poor idling.

Fouled spark plug(s).

Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty oxygen sensor.

Check oxygen sensor. (See “Oxygen 

Sensor” on page 7-6.)

Faulty ISC (idle speed control) valve.

Check ISC (idle speed control) valve. (See 

“ISC (Idle Speed Control) Valve” on 
page 7-3.)

Valve clearance adjustment.

Check valve clearance. (See “Valve 

Clearance Check and Adjustment” on 
page 5-3.)

Faulty valve spring.

Check valve springs. (See “Valves” on 

page 7-27.)

Insufficient engine power.

Fouled spark plug(s).

Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty fuel injector.

Check fuel injectors. (See “Injectors” on 

page 7-9.)

Valve clearance adjustment.

Check valve clearance. (See “Valve 

Clearance Check and Adjustment” on 
page 5-3.)

Vacuum leak.

Check intake manifold vacuum. (See 

“Intake Manifold Vacuum Test” on 
page 5-2.)

Cylinder compression leakage.

Check cylinder compression. (See 

“Cylinder Compression Test” on 
page 5-6.)

Faulty piston ring(s).

Check piston rings. (See “Connecting 

Rods and Pistons” on page 7-38.)

Faulty head gasket.

Check head gasket. (See “Cylinder Head” 

on page 7-24.)

Incorrect fuel.

Use proper fuel.

DIAGNOSTIC TROUBLESHOOTING

6-3

6

Engine surges or misses.

Fouled spark plug(s).

Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty fuel injector.

Check fuel injectors. (See “Injectors” on 

page 7-9.)

Valve clearance adjustment.

Check valve clearance. (See “Valve 

Clearance Check and Adjustment” on 
page 5-3.)

Vacuum leak.

Check intake manifold vacuum. (See 

“Intake Manifold Vacuum Test” on 
page 5-2.)

Poor throttle response.

Fouled spark plug(s).

Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty fuel injector.

Check fuel injectors. (See “Injectors” on 

page 7-9.)

Valve clearance adjustment.

Check valve clearance. (See “Valve 

Clearance Check and Adjustment” on 
page 5-3.)

Vacuum leak.

Check intake manifold vacuum. (See 

“Intake Manifold Vacuum Test” on 
page 5-2.)

Throttle body gasket leaking air.

Check throttle body and gasket. (See 

“Throttle Body” on page 7-4.)

Faulty throttle position sensor.

Check throttle position sensor. (See 

“Throttle Position Sensor” on page 7-3.)

Incorrect fuel.

Use proper fuel.

Engine overheats.

Coolant level low.

Check coolant level.

Water pump belt loose.

Check belt tension.

Faulty thermostat.

Check thermostat. (See “Thermostat Test” 

on page 5-3.)

Faulty water pump.

Check water pump. (See “Water Pump” on 

page 7-10.)

Faulty head gasket.

Check cylinder head and gasket. (See 

“Cylinder Head” on page 7-24.)

 Condition

Probable Cause

Remedy

6-4

DIAGNOSTIC TROUBLESHOOTING

6

Excessive fuel consumption.

Fouled spark plug(s).

Check spark plugs. (See “Spark Plugs” on 

page 7-8.)

Faulty ignition coil.

Check ignition coils. (See “Ignition Coils” 

on page 7-8.)

Faulty fuel injector.

Check fuel injectors. (See “Injectors” on 

page 7-9.)

Valve clearance adjustment.

Check valve clearance. (See “Valve 

Clearance Check and Adjustment” on 
page 5-3.)

Vacuum leak.

Check intake manifold vacuum. (See 

“Intake Manifold Vacuum Test” on 
page 5-2.)

Throttle body gasket leaking air.

Check throttle body and gasket. (See 

“Throttle Body” on page 7-4.)

Faulty throttle position sensor.

Check throttle position sensor. (See 

“Throttle Position Sensor” on page 7-3.)

Incorrect fuel.

Use proper fuel.

Faulty oxygen sensor.

Check oxygen sensor. (See “Oxygen 

Sensor” on page 7-6.)

Restricted air cleaner element.

Check air cleaner element.

Excessive oil consumption.

External oil leak.

Check drain plug.

Check oil pan for leaks.

Check rear main crankshaft seal for leaks.

Check front cover crankshaft seal for 

leaks.

Check front cover for leaks.

Check oil pressure sending unit for leaks.

Check oil filter for leaks.

Check cam cover for leaks.

Internal oil leak.

Check valves and seals. (See “Valves” on 

page 7-27.)

Check PCV valve. (See “PCV Valve” on 

page 7-4.)

Check piston rings/cylinder compression. 

(See “Cylinder Compression Test” on 
page 5-6.)

Check cylinder head and gasket. (See 

“Cylinder Head” on page 7-24.)

Low oil pressure.

Incorrect engine oil.

Change engine oil. (See “Change Engine 

Oil” on page 3-2.)

Low oil level.

Check oil level. (See “Engine Oil Level” on 

page 3-2.)

Restricted oil filter.

Change oil filter. (See “Oil Filter” on 

page 3-2.)

Faulty oil pump relief valve.

Check oil pump relief valve. (See “Oil 

Pump” on page 7-33.)

Faulty oil pump.

Replace oil pump. (See “Oil Pump” on 

page 7-33.)

Restriction in lubrication system.

Check/clean lubrication system. (See 

“Lubrication System” on page 4-11.)

 Condition

Probable Cause

Remedy