junito1

I just finished putting my swap in.

ANd i have 0 fuel pressure. Myt pump isnt making a single sound.(NOPOWER)

Im trying to figure out my problem.. If you guys could tell me where the circuit opening relay is on the damn car that would be greatly appreciated.

RotaryRocket88

iTrader: (7)

Best I can tell from the wiring diagram is that it or at least the plug that goes to it (F-08) is behind the instrument cluster / duct work. Maybe you can reach it from underneath. No idea.

Jumper the test connector (yellow plug at the passenger shock tower) or prop the AFM door open. See if the pump runs then.

sim_rx3

simple things first.

did you check the fuse?

if your car is a turbo version the pump should work with the relay off anyway as it has a resistor across the relay contacts as a "low speed".

when the relay is activated by the ecu when the rev range picks up the relay icloses the contacts short the resistor and runs the pump at "high speed".


so if you have no power at all..

id check the fuse first. then find the relay and check to se if the resistor is still ok.

junito1

OK this is all i have checked.

15a fuse in cabin is good. CHECK!
Main relay is good clicking when key is set to on positon. Good.
JUmped the yellow connector under the air filter and NOTHING. NO Good.
I havent found the circuit opening relay yet so I DUNNO aboiutt hat one..

OH, and i have not tried to run the pump to the battery yet... THis walbro 255 is 1 year old.. soo... COuldnt be bad.. But ill check tomorrow.
DO i jump it to the red wire?

HAILERS

Circuit Opening Relay is just above the steering column shaft. About where your knees are. Yellow in color .......I think.

The fuel pump not only gets power by the afm internal switch and the yellow fuel pump check connector, but it also will get powered up anytime the key is HELD to START. There are two relay coils in the Circuit Opening Relay. One is controlled by getting a gnd from the afm switch or the yellow check connector.

The other coil in the Circuit Opening Relay is controlled by getting POWER from the start circuit when the key is HELD to START.

Try holding the key to Start and monitor the voltage at the pump when that is done. Or listen to the pump when the key is HELD to START.

Other possible causes are a blown ENGINE fuse. It supplies power to the Circuit Opening Relay. But your MAIN Relay is pulling in so it's probably good. ENGINE fuse also powers the MAIN RELAY.

If you have the ECU grounds not grounded, then jumpering the yellow two socket fuel pump check connector won't cause the pump to work. One of those two sockets is connected to the ECU ground on top of the rear rotor housing. The other socket goes to the ground side of one of the two coils in the Circuit Opening Relay.

So try this. At that yellow check connector, jumper one of the two socket to a known ground point, like the bracket that holds the boost sensor to the chassis. Key to ON. If that does not work, then jumper the OTHER socket of that yellow connector to the same known ground point with the key ON. Pump should run.

I doubt the ENGINE fuse is bad and also don't think its the Circuit Opening Relay. Try the things I mentioned with the yellow two socket connector.

Or reach under the car and pull the small wire off the starter and then hold the key to START. Pump WILL run but only as long as the key is HELD to START. If that happens, then there is probably a problem with the ECU grounds not being grounded.

Just a GUESS.

junito1

Well you lost me a bit.. I know my gorund on top of the back iron and housing are on there for sure.

MY engine fuse 15a in the cabin is good for sure. I checked twice.

ANd i have a fuel pressure guage. WHen i try to start is keeps cranking and fuel press stays at 0.
NO matter what i tried the pump didnt make a single noise or read press ont he guage.

The whole ecu ground... thing.. IS this ground near the ecu? I have not taking this ecu out. ANd the pump worked perfect before i swap the engine.


PLease bare with me guys.. im an idiot when it comes to following schematics and wiring diagrams. Electronics period.

1987RX7guy

iTrader: (3)

Did you verify you have 12v+ at the fuel pump when you are cranking? I'd venture as much to say that if you are getting 12V or more when cranking at the fuel pump and it makes no noise you have a dead Walbro If you are not then possibly you have bad wiring in between.

misterstyx69

iTrader: (142)

Something is making me post this!
is Your AFM plugged in?.is it the correct one for the engine?
is the engine Series and car series the Same(like s4 engine in an s4 Car)?
.Lastly,maybe Hailers can confirm this:.Doesn't the Fuel pump run IF the Afm Flapper is moved?.
Like I Said,I don't know why I am throwing this in,.but it made me think that the Afm has something to do with the Pump.

sim_rx3

yes the afm does have something to do with the pump.

there is a contact in the AFM that when the engine stalls (ie air flow meter flap docks) the contact opens and turns the pump off. its a satety issue in an accident to shut the pump down.

sometimes also the plug pins gum up on the AFM.

get some electrionic cleaner spray and give the internals of the plug a hit with it and them reapply contact grease to the pins (which it is from factory).

see how that goes

junito1

BEfore everyone starts doubting anything. I have full 88 TII. Engine is an s5 with all sensors form the s4 block swapped over along with my throttle body. PLus injectors etc.

I have not tried running it direct to the beattery yet. WHIch is the color of the pumps power wire? red or blue?

IS there a plug that i could of forgot that can cause this?

junito1

I tried cranking for over 5 second ("HELD to START") and no fuel press.. Im sure the pump isnt working.

AGain my engine fuse in the cabin 15a was double checked. And the MAIN relay is clicking when key is in the ON position.

I will try everything you said tom. I uderstand what your saying now. HAd to read it like 5 more times.

junito1

HAiler. I grounded the yellow check connector. THE pump comes on.. Its barely making noise though as if it were barely working.. ANd still didnt make fuel pres on the guage.


WHere are the ecu grounds...

HAILERS

On a series four car, the ECU grounds are on top of the rear rotor housing and cannot be accessed without removing the upper intake.

I think you also have maybe another problem. I think the fuel lines where they mate to the engine. Pull the one off that comes from the fuel filter. Make sure by looking directly at the fuel filter and following the hose up to the engine. Then pull it off. Then jumper the yellow connector to ground, key ON, and see if fuel pours out or not.

Fuel hoses connect up differently on the import engines verses the USA models. Common problem with engine swaps when the engine came from JDM etc.

I'll attach a jpg of where the ECU gnd is on a SERIES FOUR car.

We've seen this lack of ground on that yellow connector, on this forum. IN that last case, if I remember right, was due to some alternation in the EM harness.

Have you made any significant changes to the harness(s)???????

The ECU ground in the jpg is on a ring terminal and is not bolted down. Just in case you wondered.

HAILERS

One thing that might have caused the fuel pump to not work when the key is HELD to START, is if someone has installed a seperate wire to engage the starter than what the stock car came with.

You know of any changes in the wiring for starting the car??????

The fuel pump plug on a STOCK car is under the carpet and behind the left rear strut tower. The LARGE BLUE wire is power. Just opposite it on the other half of that plug is a BLACK/WHITE wire on a STOCK harness.

junito1

MY fuel lines are connecting like so. FUel filter --> Aeromotive FPR(fuel press gauge) --> secondary fuel rail.

THat connector on the pic is grounded to the rear alum. housing.

As far as changes to the engine harness... My relative, ex mazda master mechanic, Had to fix the driver side harness which leads to the starter also.
BUt im not sure what was done... When i got the car back from him, the car starts without clutch also.




OH... ANd i held the flapper open on the aFm open and the pump worked.

junito1

My car is complete gutted. THE harness back there is copletely stock. The four wire plug looks to be in perfect ocndition.

On the harnes that leads to the starter looks the same. to me... THere is one little wire thats ripped... It is yellow red.. I dunno what it is..

Also, Oil pan plug.. The female side. There are two plugs right next to each other.
One connects to the oil pan plug and the other? IS just hanging there..

HAILERS

Yellow/Red is the oil pressure senders output wire.

Real odd pushing the vane aft makes the pump work. The gnd it uses comes off the ECU grounds just like the Black wire on the yellow two socket connector does. I attach a jpg of it written sometime ago. I"m not sure it'll make sense or not.

Wheter you push the vane aft or jumper the yellow connnector, you use the same ground wire to put a ground on the Circuit Opening Relay. I'm not sure what is wrong with the yellow connector now. First you jumpered it and it did not work, then you jumpered one socket to gnd and the pump worked. Odd. Can't be explained.

RotaryRocket88

iTrader: (7)

There should be a total of 6 wires (5th gear sw./rev. sw./neutral sw.) on that same section of the harness that runs down the transmission tunnel, so you can ignore them for this issue. The large positive battery lead and the small wire running to the starter solenoid are the only ones you should make sure are connected.

If the pump runs with the AFM door propped open, then your problem is with the start signal not reaching the second coil in the circuit opening relay. That'll at least give you a section of the front harness to start checking out.

HAILERS

The harness that attaches to the engine. Is it from a non turbo or turbo?

I no more think the ECU grounds are not bolted down since you pushed the vane aft and the pump worked. Hope you did't pull the upper intake off to check that out. It's probably ok.

Some cars have two sensors on the pan. Others just the oil level sensor. Don't worry about the other sensor missing. It was a oil temp sensor for the Sub Zero system that has been removed. Let the wire dangle or tie it back. I forget the colors.

By the way, for a temp fix, you could leave that wire you grounded on the yellow connector ....grounded. Then the pump will work anytime the key is to On. I said temporary til you work things out.

It's a little hard to tell you what color wire that goes to the Circuit Opening Relay from the start circuit. ON some cars it's Black/red and others black/white.

HAILERS

If a Turbo EM harness was used with non turbo Front harness then I can explain the lack of a Start signal to the Circuit Opening Relay. If you used only non turbo harness all the way, then I cannot explain the lack of a signal to the relay to pull it in when you HOLD the key to Start.

The explanation would involve the two yellow connectors in the passengers foot well that connect the EM harness to the Front harness. Not a pretty explanation either.

HAILERS

Anyway, do you now have fuel pressure ?????????

junito1

HAiler I have a full turbo II model 1988.
THe whole car should have s4 TII harness.

WHen the flapper on the afm is held open the pump seems to work harder than when grounding one of the yellow 2 socket.

I also checked the plugs on the afm.. they are pretty clean.. I dont think thats the
prob.


Rotaryrocket: Im sure the starter has the big positve and the silinoid hooked up because if they werent the car wouldnt crank? SHe cranks fine.. JUst no fuel...

I think i found the circuit opening relay.. But second coil..? And the front harness to check..

Oh boy.. im getting in deep now.. Might have to call for backup.

junito1

My car has about 1/4 tank or less. Prolly less. THe car is on stand ont he front and not on the back. SO its looking skyward somewhat.

I kept the yellow connector grounded. FOr temp use. The pump is running hard but there is no fuel press.!! WTF

Could the alternator not being hooked up hAVE ANYTHING TO DO WITH IT?

Mr.FC3s

just a quick thought did you check the fuel tank cover gasket? I have known these things to cause no fuel flow. basicly the pump makes presure to help it flow the gas out and if this gasket leaks then you get almost no gas if any to come thru the lines

junito1

Fuel tank cover gasket? I dunno where or what that is.