U2Hobo

93 Civic with a b16 swap, wire tucked running s200 on a p28.

After the wire tuck the car ran fine, had it done at a reputable shop, don't THINK its the wire tuck so please don't just say opp wire tuck must be that.


Car gets wire tuck runs for a few days
Fuel Pump goes out, replace it with a new one
Cars run fine again for 2 days
I pull into my drive way letting my car idle, just dies, i think it ran out of gas
Next morning I put a few gallons in it went to start and my pump didn't prime nor did the CEL scan
replaced main relay with a known working one, still nothing
swaped back to a stock p28 still nothing
My cel comes up and reads code 0
I have checked all fuses, my ignition switch, replaced both ecu and main relay and still nothing

When I swapped the new fuel pump I didn't disconnect the battery, could I have shorted something out?

I had one of the techs from the shop that did the tuck come by, he said I had power to the ecu, and power to the main relay and power to my ignition switch when keyed on, but no power to my pump, and that was all he really checked

So in a nut shell, main relay, pump and ecu are know working, all fuses are good, I don't know how to check the relays, when I key on to start the motor turns over, I get no spark or fuel, nothing primes, I hear a clicking in my under-hood fuse box, and my cel reads code zero I think, but im not sure if it is even scanning

dtapia

ok first of all you said no power to the fuel pump. with that alone i would be looking at broken wires or other damage.
start ohming all the input wires and out put wires to the ecu and fuel pump.
im going to say it
sounds like a wiring problem.

maybe im old but not sure why a wire tuck would be done unless you drive with the hood open and when your at a stop light people will walk by and say wow nice wire tuck ?
now my friend you have a wiring issue. time to retrace all the steps and see what was damaged.

fcm

If there is no power to the fuel pump then either the PGM-FI Main relay or the ECU is the problem, or the wiring running between them, I would drop the PGM-FI Main Relay and do some checking.

I do not have a wire diagram for a 93 civic, [PGM-FI Main Relay] but I will assume it is the same as a 93 Integra.

Black - ground and all times.
Black/yellow - 12V+, [hot in run and start], injector relay control and fuel pump power.
Yellow/black 1 - 12V+ output from injector relay, [hot in run and start] to injectors, ECU and a few engine sensors/valves, it is also power for fuel pump relays coil.
Yellow/white - 12V+ input to injector relay, [hot at all times].
Blue/white - 12V+ input, [hot in start] back up power for fuel pump relays coil.
Green/black - ground from ECU, fuel pump relay control, ground for a few sec. when priming and when engine running.
Yellow/black 2 - 12V+ output to fuel pump, [hot for a few sec. when priming and when engine running.

Try grounding the green/black directly to chassis, does fuel pump work? 94

dtapia

i have a etm
email me and i will forward the info.
fcm i think your spot on also.

U2Hobo

Alright I checked my PGM-FI Relay

Green w/ yellow 11.6
blue w/ white 0
black grounded
yellow w/ white 11.9
yellow w/ black 11.9
black w/ yellow 11.9
yellow w/ green grounded

This was done with my key in the run position

I will try grounded the yellow w/ green wire to my chassis and report back

U2Hobo

Alright I grounded the yellow with green to the chassis and same thing, when I key on to start the blue w/ white voltage is around 8.6, according to your post it should be 12+, so what do I need to do from there?

malink

I had the same problem. I rewire the wire that goes form the main realy to the fuel pump and never had a problem after...except for grounds

fcm

DO NOT ground anything, the wire colors are not the same, you will need a wire diagram for your 93 Civic.94

dtapia

sent already. he's got some home work now.

U2Hobo

Yea I noticed the colors didn't match, my fuel pump wire has zero volts, the yellow w/ green wire was to my fuel pump. I'm kinda confused I have all the correct voltages EXCEPT to the fuel pump, I'm getting signal to my pump control, my start input but not the pump

fcm

If there is no power on the fuel pump power lead then either the fuel pump relay is bad, ECU is bad, [no ground signal from ECU to fuel pump relays coil], injector relay is bad.

Try this, with ign. switch on check for power at the injectors, [wire that is the same color at all injectors.
If there is power at the injectors that means half the PGM-FI Main Relay is working...
Injector relay control input/fuel pump relay power input fuse is good, [hot in run and start].
Injector relay power input fuse is good, [hot at all times].
Injector relay output is good, [power to injectors, ECU, engine sensors/valves and fuel pump relays coil].

That leaves only the fuel pump relay, or it's inputs/outputs as being the problem.

If there is power at the injectors, try this, supply power directly to the fuel pump power lead, [yellow/green] if the fuel pump runs, try and start the car.

I will check at work this morning to see if we have a wiring diagram for the PGM-FI Main Relay in a 93 Civic.
It is important to have the correct wire colors to do a proper check. 94

U2Hobo

Alright I had a bit of time at lunch to check the power to the injectors, I have power there. When I get off I will give the pump power and see if the car will run

on-site ej1

hey bro if u still hear the noise near the fuse box under the dash, u might want to check your engine wiring harness... the person that might of done the tuck might of forgot to connect a ground wire that comes out of the engine harness.. if u find it and its not connected find a good ground and make sure its touching metal (not paint)... if it is grounded make sure its grounded good and that should be your problem.... i had the exact same problem when i did my wire tuck and was going crazy trying to figure it out! good luck and hope this works!!

rookshot06

im having almost the same prob after the tuck. all that happens is when i turn the key to ON my check engine light stays on also relay is not clicking. no power to injectors. please if some1 can help it would be great. thanks in advance for any help

so lazy

sounds to me someone has a not so good " engine harness ground " look on your Thermostat Housing on your motor see if that ground is bolted down good it should be a "10mm bolt" should be holding down some brown and black wires. kinda tough to say when you're not there to actually have your hands on the car checking it out. just throwing out options for you man. good luck

running riot

i have the exact same problem. I am not getting power from blue/white either. i ran a wire from battery to the pump and the pump works fine, even builds 50psi at the fuel gauge i got mounted on the rail. i tried starting the car and nothing. It sounds just like it does when the pump is disconnected.

I pulled out the ignition signal fuse and put the key in to crank and repalced the fuse and heard the click at the relay. i replaced the relay previously with a brand new one from honda. So im starting to think its a bad ecu then? i mean the pump works but doesn't prime, the ignition is giving a signal to the relay and the relay is brand new and no other fuses are popped. I did take the ecu signal wire at the relay and ground it and the ecu fuse popped so there is power going to the relay from the ecu and i did the same thing with the fuel pump wire and popped the fuel pump fuse. replaced both and still nothing, engine spins but wont crank. WTF im thinking the ecu went but i dunno all original harness all original wiring nothing spliced used my ex harness for a b16 swap. any ideas?

turboslut

Check fuse #9 maybe?