Geely CK Series 2007 Workshop Manual page 75

d. Fuel pressure system abnormal;
e. Idle control valve fault;
f. Vacuum pressure sensor fault;
g. Ignition system fault;
h. The compression pressure in the cylinder is a little lower;
i. Injector leakage.
3. Diagnosis and Troubleshooting
a. Perform self-diagnosis first, check whether there is any DTC, if there is, find the reason and cause by the
DTC;
b.If it is hard for cold start but easy for hot start, check water temperature sensor and intake temperature
sensor for fault;
c. If the engine can not be started quickly in hot condition, the relief of the fuel pressure will be fast, then
repair and replacement shall be made;
d. If the spark is too weak, check high pressure coil, spark plug clearance and spark plug for carbon deposit,
repair or replace them one by one after isolating the problem;
e. Intake and exhaust valve is not completely closed, piston ring failure is likely to cause low compression
pressure in the cylinder, you should carefully repair intake & exhaust valve and seat, or replace them;
failed piston ring shall be replaced.
4. Diagnosis and Troubleshooting for hard starting and trouble shooting procedure. (Figure 149)
III. Fuel Pipeline and Circuit Faults for Poor Engine Operation
Poor engine operation includes: insufficient power, poor acceleration, poor deceleration, big fuel consumption,
rough idle and Engine overheat.
1. Insufficient Power
(1) Symptom:
Engine operation is normal without load but slow at load, insufficient power when uphill and not improved
even if the accelerator pedal is completely depressed, speed can not be increased and unable to reach the
maximum vehicle speed.
(2) Causes:
a. Air cleaner is clogged;
b. Poor intake system seal;
c. Intake pressure temperature sensor fault;
d. Low fuel pressure;
e. Broken pressure adjustor;
f. Clogged injector or poor atomization;
g. Throttle position sensor fault;
h. High pressure spark is too weak;
i. Improper valve clearance;
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