Which Fuel Pump Relay...?
 

Hello!
I have recently boaught this Mercedes Benz. Problem is that my car is not performing well from day first, Engine is giving bit missing sound. My mechanic told me that I have to change the Fuel Pump Relay of my car. But he is not sure that which relay I should get him, because My Car’s body is W123 and Engine type is 102.

Currently the part number of the Damaged Fuel Pump Relay is 001 545 6705 with 9-pins.

I have check on some sites this Relay with this part # 001 545 6705 is for W123, 230E
BUT my confusion is that the role of this relay is to give fuel according to the engine’s requirement, so RELAY should be according to my Engine’s type, not according to my car’s body type.

Some Details of My Car Is
W123, Chassis number is "123223 20"
It has 4 Cylinder Engine, E230, 4-Forward Manual, Right Hand Drive
Engine type is 102

Now anyone who can guide me that which part number's relay should I use for my car?
Should I use W123 Fuel Pump Relay?
OR Should I use relay according to my Engine which is of type 102?

Dear I have 1 More Questions.....I shall be really grateful to you if you could answer them also.

1) What is the part Number of my car's Fuel Injectors?

THANKS
Tallat Hussain Ghazi