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1.2L REVOTRON ENGINE
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2.4 ENGINE TESTS AND MAINTENANCE:
A. PRELIMINARY INSPECTION
:
NOTE
It is always advisable to first use the
diagnostic tool and rectify the electrical
faults, before commencing with mechanical
repairs/ troubleshooting. Refer ENGINE
MANAGEMENT SYSTEM section in this
group for procedure.
GENERAL :
1. Check for leakage of Oil, fuel, and Coolant.
2. Check for overheating of engine.
3. Check for unusual smoke.
4. If there is any fault in the Engine
Management system
(EMS)
then the MIL
indicator in the instrument cluster will come
ON. In such a case connect the diagnostic
tester.
(For procedure refer EMS section).
Before proceeding to carry out actual
reconditioning of engine, it is desirable to
have a preliminary inspection of engine to
ascertain whether an engine reconditioning is
necessary and if so, to what extent.
Most common reasons for which engine is
reconditioned are
1. Loss of power.
2. Excessive engine oil consumption.
3. Extremely low engine oil pressure.
4. Mechanical failures.
To know exact reason and general condition of
engine, proceed as follows
i. LOSS OF POWER :
Loss of engine power may be due to
a. EMS is in limp-home mode due to some
critical fault.
b. Clogged air filter / exhaust passage /
catalytic converter.
c. Defective fuel system
d. Clutch slippage
e. Brake binding
ii. EMS is in limp-home mode :
If the EMS detects some major fault in the
system it switches to limp-home mode,
where it runs at a reduced torque. Connect
the diagnostic tester and check if any faults
are present in the Engine EMS, if found
rectify them.
(For details refer Engine
Management Section)
iii. Clogged Air filter / Loss of Charge Air
Pressure/ Choked Exhaust Silencer /
catalytic converter :
Loss of power with unusual black smoke
from engine exhaust indicates lack of air or
low air charging pressure to engine
cylinders. Clean air filter & inter cooler fins.
Check all joints for air leakage. If power loss
with black smoke is still felt, check exhaust
silencer for choking. Clean and replace
silencer if necessary. Check for kink
formation in exhaust piping.
iv. Defective Fuel System :
Check the Fuel system for fuel flow. If the
flow is restricted change the filter.
v. Clutch Slippage :
Clutch slipping can be confirmed by any of
the following two methods:
Method 1 :
1. Drive the car in 1st or 2nd gear at a minimum
speed corresponding to that gear.
2. With the accelerator pedal in a fully pressed
position, gradually apply brake with left foot.
3. If the engine stalls, the clutch does not slip.
Method 2 :
1. Drive the gear with weight equal to GVW in
3rd gear on a level ground.
2. Allow the speed to drop upto 15kmph.
3. Now press the accelerator pedal fully.
4. With slipping clutch the car will not pick up
speed, also a clutch burning smell could be
noticed.
5. If this does not occur, the clutch does not
slip.
vi. Brake Binding :
During driving apply brakes number of times
and then shift gear to neutral position and
check free rolling of vehicle. Check brake
drums/brake discs for overheating and if
necessary jack up the vehicle and check
wheels for free rotation.