Hi
Long story short
I have a 1995 Acura Integra GSR b18 forced induction tuned by hondata. All of a sudden one day my car did not start, no power to ecu or fuel pump. Started troubleshooting and it led me to find that
i had a capacitor blow on my ecu, easy fix right? Wrong.. I went and bought a brand new ecu from hondata. Car still will not start. Cleaned up every single ground on the ground and verified continuity
Led to me to further troubleshooting into the main relay.
installed a new main relay right off the bat
Diagnostic report from my multimeter
ecu power relay:
Pin 1- good battery power
pin 2- good ground
pin 5- good power from ignition source
pin 3- NO POWER coming out of relay that powers ecu

When I jump pin 1 to pin 3, the ecu powers on with fuel pump, no vehicle start tho

The coil that triggers the relay for the ecu is good, the battery power that is supposed to get transferred inside the relay is good. No power on the other side of the relay.
Im lost

 

The diagram you have is for an OBD-0 car. Here's how you test the main relay (removed from the car):

Test 1: Attach +12V power to Pin 6 and ground Pin 8 - check for continuity between Pin 5 and Pin 7. If no continuity, the relay is bad.
Test 2: Attach +12V power to Pin 5 and ground Pin 2 - check for continuity between Pin 1 and Pin 3. If no continuity, the relay is bad.
Test 3: Attach +12V power to Pin 3 and ground Pin 8 - check for continuity between Pin 5 and Pin 7. If no continuity, the relay is bad.

If you pass all 3 tests, the main relay is OK and you need to move on to checking wiring. Here is the main relay diagram from the EG Civic manual.

 

You need a proper wiring diagram, If you do not have an ETM for your vehicle then I suggest going to the sticky in this forum and purchase a diagram for your vehicle.

According to the diagram I am looking at, the relay plug is as follows:

Pin1: fuel pump control from ECM(should be ECM supplied ground when cranking or running,if the vehicle is not doing either,the ground will go away in a few seconds)
Pin2: Constant power from fuse 18 of the under dash fuse box
Pin3: Ground(G101)
Pin4: Power to the fuel pump(should have no voltage if the ECM is not grounding the relay)
Pin5: Contstant power form fuse 24 of the SRS fuse block
Pin6: I believe it is switched ignition power
Pin7: Constant power from fuse 31 of the underhood fuse box.

***edit: I should clarify the pinouts that I listed are for the plug not for the relay itself. You should be doing your testing at the plug ,with it plugged into the relay, key on,engine off***

A proper wiring diagram is essential for accurate troubleshooting. With that said, sometimes the published diagrams for these older vehicles is incorrect. Though I have rarely found that to be the case with Honda.