25 

 

Engine noise over normal level 

Exhaust system leaking or block 

Intake system leak or block 

Generator water pump, booster pump etc. 

sound abnormally 

Water tank fan and AC fan sound abnormally 

Water temperature over normal value 

Engine interferences with relevant accessories 

Compressing ratio over normal value 

Engine operates abnormal 

Check 

Check and replace 

Check 

Check 

Check 

Check and replace 

Check and replace 

Check 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Leak or block 

Over normal value 

Interferen 

Abnormal 

Abnormal sound 

Abnormal sound 

Leaking or block

Abnormal 

 
 

 

 

26 

 

No. 014 Water temperature over normal value after AC activated   

Malfunction Cause 

Solution 

Insufficient coolant fluid 

Fill coolant according to requirements. 

Radiator fan operates abnormal 

Radiator fan blade deformed and stuck. Replace radiator 
fan assembly when the fan speed is low. 

Too much refrigerant   

Check refrigerant, whether it is too much, which increases 
engine load and high water temperature. The refrigerant 
shall be filled to standard level. 

Condenser fan malfunction 

Maintain fan wire and motor. 

AC system pressure over normal value 

Adjust system pressure to normal value. 

The cooling and cycling performance of cooling 
system lower than normal level 

Too much furring contains in engine water pipe, which 
results poor water cycling and cooling, and shall be 
cleaned. Clean or replace the radiator, when it is dirty and 
blocked. 

Generator belt loose 

Adjust belt tightness according to requirement. 

Water pump operates abnormal and results 
poor cooling water recycles. 

Maintain or replace pump assembly 

Thermostat fails to open 

Replace thermostat assembly 

ECU malfunction 

Maintain ECU and all wire terminals 

Radiator over 
heated after 
AC activated 
when driving 

Engine operates abnormally 

Disassemble and maintain engine 

 

Water temperature over normal value after AC 

activated 

Insufficient coolant fluid 

Radiator fan operates abnormal 

Too much refrigerant 

Condenser fan malfunction 

AC system pressure over normal value 

The cooling and cycling performance of cooling system lower than 
normal level 

Poor cooling water recycles 

ECU failure 

Engine operates abnormally 

Drain 

Add 

Check 

Check and replace 

Check and replace 

Check 

Check 

Check 

Replace 

Abnormal 

Over normal value 

Abnormal 

Poor 

Not smooth 

Over normal value 

Poor 

Lack 

Failure 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

 
 

 

 

27 

 

No. 015 Oil pan leak   

Malfunction Cause 

Solution 

Too much oil 

Fill oil according to standard. For 4-cylinder engine, dry, 3.5L; wet, 
3.0L. For 4G18 engine, with oil filter, 4.0L; without oil filter, 3.8L. For 
3-cylinder engine, 3.0L. 

Oil pan gasket damage 

Replace oil pan gasket; tighten the bolts after sealant coated. 

Rear end cover gasket leak 

Replace rear end cover gasket and coat with sealant. 

Rear oil pipe capping leak 

Replace or maintain rear main oil pipe capping. 

There is blow hole on rear end

Maintain the blow hole on rear end. 

Oil pan bolt loose 

Tighten oil pan retaining bolt or replace damaged bolt. 

Oil pan damaged or deformed

Maintain or replace oil pan. 

Oil pan retaining bolt adjust to 4.9NM, evenly. 

Irregular assembly procedure 

Coat sealant with proper quantity, otherwise, the gasket may slid and 
move. 

Unplug or replace gas exhaust system (PCV valve) 

Inner engine pressure over 
normal value 

Engine cylinder, piston ring and piston worn out. Maintain or replace 
relevant component when necessary. 

Oil leak at rear end of 
oil pan after vehicle 
parked. 

Crankshaft rear oil seal ageing 
or damage 

Replace crankshaft rear oil seal. 

 
 

 

 

28 

 

Oil pan leaking 

Too much oil 

Oil pan gasket damage 

Irregular assembly procedure 

Oil pan damaged 

Rear end panel deformed or seal gasket failure 

Rear oil pipe capping leaking 

Oil pan bolt loose 

Inner engine pressure over normal value 

Cranksahfe rear oil seal ageing or damage 

Remount 

Fill oil according to standard 

Check 

Check and replace 

Check and replace 

Tighten 

Replace 

Replace 

Replace 

Abnormal 

Over normal value 

Blocked 

Too much 

Damage 

Irregular 

Damage 

Abnormal 

Loose 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal 

Normal