Valkyrie

Ok, I find that my fuel pump doesn't budge when I crank the car...

I tried it out of the car with a battery (and a bucket of water) and it worked fine... stick it in the car and nothing... and no voltage to it either.

Checked the "ENGINE" fuse, it's fine... so what else should I check before I tear my interior apart and try to rewire the fuel pump?

Underhood fuses are fine.

I know there are rewiring guides for the TII... but none that I know of specifically for an S5 N/A.

Any help?

HAILERS

Try jumpering the Fuel Pump Check connector near the right strut tower/afm area. Yellow in color. Two socket. Floats around and not tied to anything.

With it jumpered and the key ON, do you now have 12v on the pump and the pump running? Should.

Still no pump action? Take a look at the Circuit Opening Relay just above the steering column. I don't know about series five, but the BLACK/WHITE wire should have 12v on it with the key to ON. Heck, check all the wires on that relay. Take a look at the series five wiring schematic. It's online somewhere in PhotoAlbum on this site.

idsigloo

Not very difficult to rewire... If it's stock wiring you should rewire it anyways.

Valkyrie

I've been trying the jumper deal all day... no beans.

I think I'm gonna have a hard time getting the interior trim out of the way with all those damn plastic pins, etc...

Well, where does the wiring go to anyway? Guess I'll take a look at the wiring diagram...

Is the fuel gauge supposed to work when the car is ON but not started? Because mine isn't, and the tank is a little less than half full. I noticed the insulation in the pump assembly was a bit frayed... but I don't know if that's the cause or not... it's not crossed at least.

HAILERS

The fuel gauge works with the key to ON.

The ENGINE fuse in the interior fuse box feeds the Circuit Opening Relay and the Main Relay. The ENGINE fuse gets its power from the IGNITION SWITCH. The IGNITION SWITCH gets its power from the MAIN FUSE in the engine fuse box. The MAIN FUSE is good if you have signs of power anywhere else.

You've a odd problem. I'm starting to think you have no power from the IGNITION SWITCH for one reason or the other. Answer this: Do you have the IDIOT LIGHTS when the key is to ON? Make sure the small plug is on the alternator before you say one way or the other. Got a meter??? Digital????

Valkyrie

Yeah, *everything* electrical works, including the broken coolant level sensor (buzzzz). (Except for the fuel pump and the fuel gauge, and apparently the oil pressure gauge, according to the former owner)

I just bought a digital multimeter today since the analog one I had was for high voltage (150-600).

Tommorow I'm gonna take the interior trim apart, and check the fuel pump wiring harness section by section... If there's no continuity from the shock tower connector to the pump connector, for example, I'd rewire it.




One thing, you should be able to feel the vibrations of the pump when you're holding it in your hands, right? I didn't feel ANYTHING, not even the torque it creates when my sister was cranking the car for me, although I wouldn't have been able to hear it over the sound of the car cranking anyway.

Valkyrie

Ok, question: are there any inline fuses for the fuel pump harness? Maybe they were blown by the pump straining with the clogged fuel filter?

I find it strange that the wiring for the fuel pump would just happen to go bad at exactly the same time that the car was last driven, after it overheated (need to replace the coolant seals after I get it running...). Or that it was still running with that fuel filter...

HAILERS

The previous owner might have made a Fuel Cut Switch. Most people locate it near the key switch or around that plastic surround. Others locate it ????? One way to tell is to find the Circuit Opening Relay. You have to remove the plastic a/c vent below the steering wheel and look upwards. Just above the steering Column there is a relay. I tHINK, yellow in color. If you see some aftermarket wiring in that relay area, try to follow it to the cut switch.....if there is one.

There are NO other fuses involved.

I'd REALLY try to find that Circuit Opening Relay and pull it out of its socket. Then with the key to ON, check for 12v at the black/white wire in the relay base. IF you find NO voltge anywhere, then I'd say for some reason there is no 12v coming from the ignitiion switch.

I think there is a fuel cut switch there SOMEWHERE.

Valkyrie

S5's don't need fuel cut switches... at least not for flooding. I'd be pretty surprised if there wa s a fuel cut switch.

But I'm gonna check the relays (circuit opening and fuel pump) like it says in the manual tommorow... and then the wiring, and rewire anything I find to have no continuity with 12-guage wire, probably. Maybe a wire just snapped off somewhere down the line.

You should see the coolant level sensor's wire though... it's made of two different kinds of wire, not including the sensor's wire.

Is there a way to make sure the pump is grounded properly?

HAILERS

He could have installed one out of ignorance (why's everyone looking at me?). Gone.

HAILERS

An apology is in order. I forgot about series five fuel pumps etc. I don't own one for one reason, so I looked at the copy I made of the series five elec schematics.

There is a Fuel Pump resistor and relay. It is in the front of the engine bay. On the right side in front of the AFM/filter assy. Pull the plug off. There should be 12v on the L/R (blue/red) wires in the connector IF the fuel pump check connector is jumpered and the key is to ON.

Try to find the schematic on this site. They are in a PHOTOBUCKET or some device like named. See page B-3. Sorry 'bout that. After the 12v gets to the Fuel PUmp Resistor Relay from the Circuit Opening Relay, it goes to the rear to the fuel pump connector under the left rear strut towers carpet.

HAILERS

Here is where the schematics are https://www.rx7club.com/forum/showth...ht=photobucket the fuel pump schematic is on page B-3 about thirty or fourty pages into the thing.

HAILERS

Here's a S5 fuel schematic in black/white.

Valkyrie

Turns out the fuel pump connector was unplugged Fuel pump and gauge work now.

Well, now that the fuel pump runs, it still won't fire up...

and it doesn't seem flooded, since I've been turning it over with the top plugs (maybe it's better to use the undo the bottom plugs?) out, and there isn't anything coming out (except a bit of mist)...

and it does have spark and compression... so...

HAILERS

Not even a hint of it firing once in a while? No? Got fuel, got spark. Flooded perhaps??? Yes. But you know about flooring the pedal for a series five, so that eliminates flooding sort of.

Timing?? Possible.

I'm a believer in starter fluid and an unplugged fuel pump myself.

I'd check the timing myself and if it was good get a can of starter fluid and unplug the fuel pump.

Did the previous owner put the sparkplug wires on right?

Valkyrie

Now it runs just had to use some MMO, starting fluid, and crank it for about 20 seconds straight (not including the other times I tried)

crazy idle though.