Wiring

[jsloden]

Hey guys, I am on the verge of getting this thing started. She starts and runs fine on starting fluid. For some reason though the fuel pump is not getting any fire. I checked the plug and there's no current getting to the pump. Having said that there are a couple of wires that are not actually going anywhere that I was hoping I could get some help with. Behind the driver's seat there's the little relay next to the lamda unit. Someone had cut the brouw wire out of the plug and spliced in another wire that doesn't actually go anywhere. I was going to splice the brown wire back into the plug like it's supposed to be but then I have no idea what actually plugs into it. I'm talking about the little plug with the brown and white wires. Then again, none of this maybe factory. Please let me know if it isn't. The second wiring problem I'm having is that there's a plug up front by the fans that isn't plugged into anything. I was hoping this might be the reason for my dead pump. It is a brand new pump and sending unit by the way. The all-in-one unit. I've included pictures to maybe clarify a little better.

4414644147

[hmcelraft]

The relay thing in pic 1 looks like a radio antenna relay to raise and lower a power antenna - disconnected. The other connection in pic 2 appears to be the brake master cylinder cap connection that senses the brake fluid level. Is that picture taken in that area?

[Christian Dietrich]

Also check your inertia switch located on the driver side floorboard on the left hand side kick panel next to the trunk release. I believe if memory serves me correctly it is grey. If that is burned up looking or not connected that won't operate the pump, also check the black plunger on top of it. I believe if its inwards, that kills the pump aswell.

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[content22207_2]

44159

IIRC the Inertia Switch was relocated during production. Early cars have it near the pedal cluster. Later cars have it against the side wall. Plunger up disconnects the pump ground.

Bill Robertson
#5939

[Jonathan]

If your fuel pump isn't getting any power, than that needs to get sorted out first of course.

Jumper the pump to come on manually at the RPM relay. Then, depending on what happens, start working your way through the circuit to find out what's not right.

Look in the resources section here in the forum for the wiring diagrams for each major area as well as the overall colour diagram for the whole car.

Inertia switch could be it as mentioned. The way to remember whether that plunger should be up or down when driving is to remember it needs to be always pointing in the direction of gravity, i.e. towards the ground. So, when you're driving normally it should be in the down position and running the pump. If/when your car is ever upside down, then the plunger should be pointing up (at the ground) and shutting the fuel pump off. Simple enough?

[jsloden]

So I guess the relay in pic 1 isn't original? Out it comes then. I'll try to get the other plug connected back up tomorrow. I'll also start tracking down fuel pump issue. Thanks for the tips guys, you've given me several really good places to start.

[Jonathan]

So I guess the relay in pic 1 isn't original? Out it comes then. I'll try to get the other plug connected back up tomorrow. I'll also start tracking down fuel pump issue. Thanks for the tips guys, you've given me several really good places to start.

The relay in pic 1 is original and it is for the power antenna.

Similar discussion here: http://dmctalk.org/showthread.php?13877-Wiring-Disaster-and-bad-pin-31-ECU-ground&p=200071&viewfull=1#post200071

[content22207_2]

Look at the wiring schematic in Post #4 -- I annotated where each component is located (I also added the harness connector under the windshield washer reservoir -- that's another potential trouble spot).

Bill Robertson
#5939

[jsloden]

The inertia switch was indeed up, so that was pushed back down. Unfortunately that wasn't the only problem as it's still not getting any power. That's odd about the relay. I don't have a power antenna, and the car still gets radio reception. I'm going to try and get the other plug re-connected shortly and see if that plays into the problem with the fuel pump. I'll also get the relay checked out. Thanks for all the replies.

[Bitsyncmaster]

The inertia switch was indeed up, so that was pushed back down. Unfortunately that wasn't the only problem as it's still not getting any power. That's odd about the relay. I don't have a power antenna, and the car still gets radio reception. I'm going to try and get the other plug re-connected shortly and see if that plays into the problem with the fuel pump. I'll also get the relay checked out. Thanks for all the replies.

You have to jump the RPM relay or have the engine running to get pump power.

[jsloden]

Got those issues figured out. Car starts but doesn't seem to be getting enough gas. Got the fuel pump working though. One last plug though. There is a plug on the front of the engine by the throttle assembly. Half of it is white and half of it is black. The white half of the plug seems to plug into the throttle assembly. There doesn't seem to be anything for the black half to plug into though. Or does it just remain empty.

Thanks

[nullset]

Got those issues figured out. Car starts but doesn't seem to be getting enough gas. Got the fuel pump working though. One last plug though. There is a plug on the front of the engine by the throttle assembly. Half of it is white and half of it is black. The white half of the plug seems to plug into the throttle assembly. There doesn't seem to be anything for the black half to plug into though. Or does it just remain empty.

Thanks

Does it plug in to a small switch? If so, the second wire is only used for automatics. It's the WOT kickdown switch.

[Jonathan]

This wiring and these switches have come up a few times recently.

More discussion, pictures and links here:

http://dmctalk.org/showthread.php?13810-Idle-Switch-Wiring

EDIT to question about car not getting enough gas:

What is your idle/tachometer doing once you get it started, but when you feel like it isn't getting enough gas? Getting the cars to idle correctly is a common challenge, but can be a good thing as it might mean you're getting pretty close to having it run well.

[jsloden]

Does it plug in to a small switch? If so, the second wire is only used for automatics. It's the WOT kickdown switch.

Thanks, that sounds like it. There's just nothing for it to plug into. That would sense given that mine's a manual.

Thanks

[David T]

If it seems like it is running too lean make sure the frequency valve on the front right valve cover is buzzing. That valve is part of the Lambda system and it adds just enough fuel to the mixture to make it the correct ratio of air and fuel. Try taking the plug off of the valve and putting it back on a few times. Sometimes that is all it takes to clean up the connections and make it work. Also make sure it is grounded. Often while working in that area the wire gets forgotten and left disconnected. Do NOT try adjusting the mixture screw to make the car run richer. Another cause for running too lean is vacuum leaks. Got to find and fix any.