Symptom
Poor idle speed, malfunction etc
Symptom
Fail to start5-125 Repair precautions:
1. according to engine requirement, electric fuel pumps with different flows are available, they have the same
appearance, mountable fuel pump may not be exactly suitable, during repair, part number of fuel pump used must
be consistent with original one, wrong replacement is not permitted;
2. in order to prevent fuel pump from damaging, please do not run it in dry state for a long time;
3. in case fuel pump needs to be replaced, please pay attention to clean fuel tank and pipeline and replace fuel
filter.
(2) Simple measuring method:
(Remove joint) turn digital multimeter to ohm position, connect two meter pens with fuel pump pins
respectively, measure internal resistance, it should not be zero or infinite (namely not in short circuit, open circuit
condition).
(Connect joint) connect fuel pressure gauge on sucker, start up engine, run the engine at idle speed, now fuel
pressure of engine should be about 260kPa; unplug fuel pressure regulator vacuum tube, now fuel pressure should
be about 300KPa.
11. Canister control valve
(1) Canister in fuel evaporation control system adsorbs oil vapor from oil tank until saturated. Electronic
control unit controls opening of canister control valve, fresh air and saturated fuel vapor in canister form
regeneration stream, which is led into engine intake pipe again. Electronic control unit changes duty ratio of pulsing
signal to canister control valve solenoid according to different operating conditions of engine, thus controls flow
of regeneration stream. In addition, this flow is also influenced by pressure difference at both ends.
Possible cause
Entering of foreign matter into valve inside results in
corrosion or poor leak tightness etc
Repair precautions:
1. To install, airflow direction must meet the specification;
2. when black granules inside valve body result in malfunction of control valve, and control valve needs to be
replaced, please check the condition of canister;
3. avoid water, oil etc liquids from entering valve as far as possible during repair;
4. in order to avoid transfer of solid-borne noise, it is recommended to install canister control valve suspending
on the hose or use soft rubber to fix.
(2) Simple measuring method:
(Remove joint) turn digital multimeter to ohm position, connect two meter pens with canister control valve pins
respectively, rated resistance at 20°C is 22 - 30 ohm.
12. Ignition coil
(1) When earthing channel of primary winding is connected, this primary winding is charged. Once ECU cut
off primary winding circuit, charging stops, high voltage is induced in secondary winding at the same time, so spark
plug discharges. Ignition coil ZSK 22 (both ends of 2 secondary windings are connected with a spark plug
respectively, so these two spark plugs ignite simultaneously.
Possible cause
Too heavy current leads to burnout, damaged by external force Repair precautions: it is prohibited to use "short circuit ignition testing method" to test ignition function, soEngine EFI System-
Engine EFI System
