Chery A15. Manual - part 26

counter-clockwise, slowly bring forward fuel 
pump assembly. 

——

Pull out fuel level sensor with little upwards 
strength. 

 

 

 

Installation of accelerator cable: 

——

Install rubber jacket on vehicle front 

boarding. 

——

Thread accelerator cable through rubber 
jacket, then push it to right position. 

——

Install hook of accelerator cable in gluey 
block of accelerator pedal. 

——

Install the other end of accelerator cable on 
throttle valve rocker of throttle valve body. 

——

Adjust degree of tightness of accelerator 

cable, located by locating clamp. 

 

 

Caution 

·When adjusting degree of tightness of 

accelerator cable you should ensure 
that: Accelerator pedal doesn’t need 
any part of empty stroke at idle; when 
throttle is full open, accelerator pedal 
limiting screw assembly is effective 
(accelerator pedal can step on 
accelerator pedal limiting screw 
assembly). 

 

 

Adjusting of accelerator cable: 

Range of free travel : 1.0～3.0mm

 

 

 

 

 

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OPERATION CONTROL OF ENGINE FUEL SUPPLY SYSTEM 

 

1. Start engine: 

In start process, ECU firstly inject to all cylinder at the same time to shorten start time. After 
that, ECU will inject according to phase order. 

 

2. Acceleration: 

In acceleration process, ECU will add injection fuel by engine requirement and deal with 
sensor signal below: throttle position, absolute pressure, upper dead center/ speed sensor, 
multiply “basic” fuel injection time by a modification factor, which is calculated from engine 
cooling temperature, throttle opening speed, and intake manifold pressure increment. When 
injector is closed and if calculated injection time has a sudden change, ECU will add injection 
Fuel by the modification factor mentioned above, that is to re-open injector (extra pulse) for 
compensating fuel as soon as possible. In order to make vehicle more comfortable, torque 
control strategy doesn’t affect performance and fuel consumption in accelerating by adjusting 
spark advance angle. Because exhaust regulatory become much more Stricter, a kind of much 
more complicated active manage strategy is developed, which utilize some physics and 
hydrokinetics phenomenon (such as fuel film mode) to gain not only a sudden change in 
throttle air input but also steady air fuel ratio. 

 

 

3. Deceleration: 

In deceleration process, fuel engine needed is decrease to reduce pollution, ECU identifies 
the phase by that throttle potentiometer signal change from high level to low level but do not 
back to idle. Furthermore, it can adopt dashpot strategy to decrease output torque (reduce 
engine brake), when throttle potentiometer signal shows that throttle is closed and engine is 
in very high speed, ECU considers it’s satisfied condition that ECU will minish by-pass air 
input by controlling step motor step by step.   

 

4. Cut off: 

ECU will adopt cut off strategy when ECU identifies that throttle is in idle position (throttle 
potentiometer signal) and hot engine speed exceeds 1500r/m. The warm up strategy is 
determined by the speed when engine coolant temperature increase strategy is running. Fuel 
will be supplied again to system if throttle is not closed and hot engine speed is lower than 
1400r/m. In high speed, ECU will adopt cut off strategy (part cut off) if throttle is not closed 
completely but manifolds pressure is very low. 

 

 

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5. Full load: 

In full load status (distinguished from throttle potentiometer and absolute pressure sensor), 
ECU obtains maximal output power by increase basic fuel injection time, while temperature 
of catalysis converter is kept in prescriptive range. 

 

6. Air pressure modification: 

Air pressure will change with different altitude, which will cause change to volumetric 
efficiency. That is why basic specified parameter (fuel injection time and by pass air input) 
need to be modified. Fuel injection time modification and by pass air input compensation is 
decided by altitude change, and ECU will refresh those parameters automatically when 
start, or does dynamic modification (air pressure dynamic modification) on a certain 
throttle position and engine speed. 

. 

7. Engine speed limitation: 

When engine speed has exceeded “critical” value for 10 seconds or instantly exceeds a 
certain value prescribed by manufacturer, ECU will cut off fuel injector control function. 
ECU will rebuild fuel injector control function when speed comes back to normal value. 

 

8. Fuel pump: 

- When engine speed is lower than a certain value close fuel pump (approx, 50r/m); 

- Open ignition switch for 2 seconds, but engine does not start fuel pump; 

- Fuel pump keeps working when engine is running or vehicle is in its way. 

 

9. Self adapting: 

ECU has self adapting function for air fuel ratio. ECU can store difference between basic 
pulse diagram and oxygen sensor modification factor continuously generated in running. The 
difference will be permanently stored because of ageing of engine and system components. It 
permits system to amend engine and components as new. 

This function includes automatically consistency test and automatically diagnosis for stored 
parameters, special diagnosis instrument can delete those parameters, and modification 
parameters will not be lost if batter or ECU is cut off.    This strategy is ineffective if canister 
solenoid valve is open. After changing ECU,    it should run at idle (warm up) for some time 
to make ECU restore modification parameter. When engine is in high speed, modification 
parameter in memory is the parameter of normal running condition. ECU another self 
adapting function can modify step motor opening degree change caused by throttle leakage 
and engine natural ageing. The self adaptive parameter will be lost when power off or ECU is 
cut off. 

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10. Electric power balance: 

Normal working of electric components (front light, heat back window, etc.) will make 
battery voltage lower than 12.2V, electric components power demanded in that time is larger 
than electric power from generator. That is to say, negative “electric power balance” may 
cause damage to battery. In that condition, ECU accelerates idle speed step by step (from 800 
r/m to 1200 r/m) to make adequate electric power from generator. Accelerating idle will 
disappear when “electric power balance” is positive. 

 

Fuel supply system of this vehicle is belonging to “half no scavenge fuel”, there is only one 
tube connecting fuel tank and fuel rail. 

This system has advantages below: 

- When accident occurs, no scavenge fuel tube can lower fire possibility to minimum. 

-There is comparative less fuel vapor in fuel tank. 

- Fuel temperature in fuel tank is lower.

 

 

 

FUEL SYSTEM WORKING COMPONENTS 

Fuel Injection Volume Inspection 

Warning： 

·Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious 

injuries or death and damage. Always carry out the following procedure with the 
engine stopped. 

 

Note  

·If there is an after market fuel injector tester, perform the following test. 

·If there is no an after market fuel injector tester, perform “Operation Test”, 

“Resistance Inspection”, and  “FUEL Leakage Test”to verify the fuel injector is 
ok or not.

 

1．Complete the  “Before repair procedure”   

2．Disconnect the negative battery cable.   

3．Remove the fuel injectors. 

4．Connect the fuel injector to the fuel injector tester.   

5．Measure the injection volume of each fuel injector using a graduated container.

 

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