1995 Del Sol S, 1.5L, Stock.
Been sitting up for a long time and we are not getting fuel to the front. We have the fuel filter off. We have done the following:
-New Battery
-New Fuel Pump
-New Fuel Relay
-Drain and cleaned tank
-New gas
-Cleaned electrical connections at fuel pump.

Any suggestions?

 

With a multi meter and the ignition on test to see if the fuel pump is getting power

 

CEL stays on steady with key turned to ON(II)?

 

When you turn the key on the CEL should come on then go out. During that time the main relay should be turning the fuel pump on and then back off. Also if you turn the key to "start" (disconnect the starter small wire so it doesn't actually crank) the pump should run for as long as you hold the key there.

Do you hear the pump run? If you hear the pump run but no fuel flows the line under the car could be blocked. Test by disconnecting both ends and try to blow air through it.

 

No power to the fuel pump. We checked the pump out of the tank and it is working correctly.

The CEL is steady.

I read somewhere to jump 5 & 7 at the relay plug so I tried that, but still got no power at the pump.

 

^With key in ON(II)? If so, check whether dash fuse 24 is blown.

Does jumping pin 1 to pin 7 make pump run?

 

We checked all of the fuses and they all appear to be good, We have the pump disconnected and are using a test light at the plug for the pump. Jumping 5 to 7 gets us power to the pump with the key on (keyed power) and jumping 1 to 7 gets us power to the pump with the key off (constant power). The relay sounds like it is working correctly. With the relay (new) installed, we don't get power to the pump at all.

 

If getting power to the pump does not result in the pump running, then check the fuel pump ground wire and its attachment to the chassis.

But there also may be a second problem at main relay or ECU.

 

The problem is not with the pump itself, (the pump runs when tested on the battery) it is getting power to the pump. What next?

 

Next:

Describe the exact test you did in 1. The solution to your problem will become evident by your answer.

 

We pulled the ECU out and opened it. It looks really good. No burn marks or corrosion on plugs or pins or inside the ECU.

Main Relay?

 

The pump was mounted in the cage and we used wire/connectors to connect it through the harness plug. Touch the wires to the battery and the pump works. We have been using a test light (chassis ground, prong in the positive side of the harness plug to the fuel pump) to determine whether there is electricity at the pump.

 

Correct me if I'm wrong.

1) You unplugged the fuel pump connector and touched (+) and (-) wires directly from the battery to the corresponding pump pins, and the pump ran.

2) When you supplied 12V to pump by jumping 1-7 or 5-7, the pump did not run.

If this^ is correct, the ground wire to the pump is bad.

 

We touched the wires to the fuel pump connector. The pump works and the ground is good (we cleaned that well). The pump is not the problem.

The problem is that we are not getting power to the pump harness/connector. When we jump 1/7 or 5/7 we get power to the pump harness/connector. The relay is new (and both it and the old relay sound like they are working). When we have the relay in place and turn the key to run, we don't get power to the pump harness/connector.

 

Does the pump run when you do these^ two separate tests? It should.

 

Yep.

 

Thanks.

Reconnect everything.

Unplug ECU connector A.

Turn key to ON(II).

Use a wire to ground pin A7 (Grn/Yel wire) in free ECU wire harness connector to metal frame under dash.

Does pump run as long as A7 is grounded?

 

Yes! that makes the pump run.

 

This^ places the fault on the ECU side rather than the main relay side.

Turn key off.

Unplug ECU connectors A and B.

Check whether pins A26 (Blk/Red), B2 (Brn/Blk), A23 (Blk), and A24 (Blk) have continuity to body ground.

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Turn key to ON(II).

Check whether pins A25 (Yel/Blk) and B1 (Yel/Blk) read battery voltage to body ground.

 

 

Describe how you are doing the continuity to body ground and voltage to body ground tests.

 

Set the meter to 20KOhms and pushed positive in the ecu plug and black to a known good ground.

 

Set meter range to Ohms not 20K-Ohms for test. Post Ohm readings.

Verify pin locations in connectors using diagram in my last post.

Was key in ON(II) for voltage tests?

 

I haven't said yet, but thank you so much for your help. It has kept me moving forward. Below is the info I put together.


Continuity
A-26
A-23
A-24
B-2
Key off and key on were all 1 on the ohm meter

voltage test
B-1
A-25
Both were 0

We did test body ground to body ground and the multimeter (set at ohms) indicated 0
We tested the battery with the multimeter and it was 12.2
below is the multimeter we are using

 

My pleasure

Set the meter to the 200 Ohm scale.

Touch the meter probes together. What is the reading?

Then make the readings above again.

This seems to be a problem. Were the wires at these two pins Yel/Blk?

Now move to the main relay connector, but do not unplug it.

What voltage do you read at main relay connector pin 3 (Yel/Blk wire)?