The steps to check and replace the fuel injector are as follows: Here we take the Volkswagen Jetta as an example
1. Inspection of fuel injector
(1) Connect the fuel injector tester V.A.G1322 to the fuel injector, as shown in Figure 1-82.
(2) Press the pump rod, and when the injection starts, read the pressure value of the oil pressure gauge.
The injection pressure of the new injector is 19~20MPa, and the injection pressure is 17MPa when the injector reaches the wear limit.
If the injection pressure is lower than the limit value, the injector should be replaced. When testing the injection pressure of the injector, the injection port cannot be in contact with hands. Otherwise, the high-pressure fuel can cause serious injury to the opponent.
(3) Press down the pump rod and maintain a pressure of about 15MP for 10s, and there should be no leakage from the injector. If the injector is leaking, it should be replaced.
2. Replacement of fuel injector
(1) Remove the upper body of the intake manifold.
(2) Remove the fuel injection pipe with an open ring wrench 3035.
(3) Unscrew the fastening nut, remove the bracket, and take out the injector.
(4) Replace the heat insulation pad between the injector and the cylinder head.
(5) Install a new fuel injector.
(6) Check the seat and install the injector correctly on the cylinder head.
(7) Install the bracket, and the tightening torque of the bracket bolts is 20Nm.
(8) Install the fuel injection pipe, and the tightening torque is 25Nm
(9) Install the upper body of the intake branch pipe.
