DIZSTRICTxB3A5T

So basically replaced motor with with b18b

New:
Clutch
Distributor
Alternator
Main relay
Fuel pump

But yet when I crank the car it cranks but fuel pump is not priming at all, when I bypass the relay direct I hear the fuel pump working but no gas is coming thru I just hear the pump buzzing.

1991 integra ls
5speed

el crapitan

do you hear the 3 clicks from the relay with key on? last click accompanied by the cel shutting off?

DIZSTRICTxB3A5T

no clicks at all on the relay and i bought 3 new relays.

B20ztek

iTrader: (1)

Relay must not be getting power, thres a few threads on here on how to check ill see how if i can find them..

el crapitan

check/clean the thermostat housing ground cluster

DIZSTRICTxB3A5T

What is the thermostat housing ground cluster and thanks if you can find the thread that would be very helpful, would having a bad ecu cause the problem as well or no? Changed everything but the ecu

el crapitan

it could. but you've already replaced enough parts without confirming.
have you checked the ecu fuse?
ecu ground is located at the thermostat housing. follow the lower rad hose to the passenger side of the head. the housing it connects to is the thermostat housing. there is a ground cluster bolted to that housing. check/clean the connection.

check ecu fuse
check/clean ecu ground cluster

if problem persists, we can move onto further diagnostics

Rushintegra

If the ground is ok then get a diagram of the fuel pump relay circuit and see witch wire is the signal wire from the PCM to the relay and see if thier is a signal ( voltage ) if not check for a loose connection at the PCM and if you have continuity on the wire to see if thier is a break in the wire somewhere.

el crapitan

^^but check the fuse first lol.
you can scroll down to about 2 thirds down the page of this article to test for power at the relay
http://techauto.awardspace.com/mainrelay.html

fcm

As mentioned, yes the problem may be the ECU/ECM.

I also agree you need to confirm power and ground at the PGM-FI Main Relay, if there are no "clicks" from the relay at all then it can only be a bad ground, no switched power, ["true ignition" hot in run and start] or a bad relay, since you have replaced the relay it has to be one of the other two.

All you need is a 12V test light, [not the LED type] to do any testing for the fuel supply electrical system, you do not even need a wiring diagram, although it would help.

Start testing by unplugging the PGM-FI Main Relay, probe all the terminals and you should find one (1) lead that is 12V+, [if not you have found the problem] turn the ign. switch on, to the run position, and probe the terminal again, there should now be a second lead with 12V+, [if not you have found the problem] turn the ign. switch to the start position, [if you unplug the starter lead from the starter solenoid the engine will not crank during testing] there should now be a third lead with power, [check the first two to make sure they also have power when ign. key is in the start position, [if no power on 3rd lead, you have found the problem, if no power on one of the first two the problem is the ign. switch.

If all 3 powers are good test the black lead(s) for ground, connect test light ground to the first power lead, [the one that is hot with ign. switch off] touch test light probe to the black lead, the test light should not work if you had all 3 powers.

Plug the PGM-FI Main Relay back in and hang on to it as you turn on the ign. switch, if you have the 3 powers and the ground there should be at least one "click" from the PGM-FI Main Relay, [fuel injector relay turning on] you can confirm this by checking for power at the injectors, [the lead that is the same color at each injector should have 12V+ on them], you also need to confirm 12V+ at IPG1 and IPG2 at the ECU/ECM, IPG1&2 will be the only two leads at the ECU/ECM that are the same color as the power lead to the injectors, both IPG1 and IPG2 must have power on them when ign. switch is in the run and/or start position.

Assuming all the above is correct, [you have the 3 powers, the ground is good, there is one "click" from the PGM-FI Main Relay when you turn the ign. switch on] it would point to the ECU/ECM as the problem, to test you can use the test light, ground the test lights ground clip, with the relay plugged in and the ign, switch on, stick the test light probe into the ECU/ECM control lead terminal, [which one you ask, that will depend on what dash harness you have] if it is the 91 LS then it is a green/black, if not, it's easy to find.

You have the three powers, the black ground, and if the relay "clicks" one time there is a 4th power, [injector relays output], that leaves you with two leads, ECU/ECM control lead, [which is a ground not a power] and the fuel pump power lead which will bew a yellow/black or maybe a yellow/green if not the 91 LS harness.

It makes no diff. stick the test light probe into one of them, if no click from the relay stick the probe into the other lead, if there is a click from the PGM-FI Main Relay but you do not hear the fuel pump running the ECU/ECM is not the problem, if you do hear the fuel pump running, the ECU/ECM is the problem.

With the test light probe still in place, [and if pump is running] try and start the car. 94