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Wait to start light and no power to lift pump


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So I replaced the fuel lines from the injector pump to where it T's off to the back of the motor and then the fuel return line. I went to replace the fuel pump with a drp2 but the connections are different (mustvhave been replaced at some point)

Anyways. I go to start it after and nothing. No wait to start light and no power to the pump. No codes.I wired the pump to the battery and it will run. I also tried to put in a new relay switch drawing power from the brown/white wire going into the PCM and still nothing.

I then replaced the ECM with a good used one and at the same time replaced the alternator in case there was any noise. Turned it on today and nothing. Still no power to the loft pump and no wait to start light and still no codes.

Anyone else have some siggestions?

Is it relatively easy to take out the whole wiring harness to check for bad wires?

When I turn the key into the on position there is a pulsing type noise coming from beneath the battery. I think it's just the cruise control? (I unplugged that vaccum line due to a leak)

Thanks everyone. Almost at wits end here

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4 hours ago, Petelightning said:

No wait to start light and no power to the pump.

 

Does it come on eventually? Sometimes when the ECM memory is damaged and it takes 60 seconds or more to boot up and trigger the WTS light. If the WTS  not coming on double check fuses.

 

ECM will not power the lift pump till it boots up and triggeers that WTS light. It will not even start till that WTS light is on. This is a sign the ECM is booted up and functional without the WTS its braindead.

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It does not come on eventually with either ECM I have. 

All fuses seem fine and I have swapped out the Fuel system relay and it works fine. 

I have cleaned all battery grounds and the ECM ground behind the starter.

The orange/black wire from the ECM harness seems to be in good condition as far as I can follow it

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2 hours ago, Mopar1973Man said:

ECM ground is the passenger side battery terminal. That ground is the lift pump. The relay is for the VP44.

I had only read that there is a ground behind the starter. I will double check the the ground off the passenger battery. The terminals are clean

there is no relay or fuse for the lift pump. So what fuses are you telling me to check?

 

Yes. Everything else seems to be fine. All dash, lights, wipers etc and it turns over as usual

 

thanks guys!

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On 2/17/2018 at 5:10 PM, Petelightning said:

there is no relay or fuse for the lift pump.

 

That is correct. The ECM is in direct control of the lift pump. If the WTS light is delaying then the ECM is NOT booted up and ready. So the lift pump will not fire. The ECM must boot up first for the lift pump or the VP44 to fire. 

On 2/17/2018 at 1:39 PM, Petelightning said:

It does not come on eventually with either ECM I have.

If the WTS light doesn't come on the ECM will not start either the VP44 or the lift pump.

 

On 2/17/2018 at 1:39 PM, Petelightning said:

I have swapped out the Fuel system relay and it works fine. 

That relay is the power relay to the VP44 again its controlled by the ECM on turning on the power to the VP44.

 

On 2/17/2018 at 1:39 PM, Petelightning said:

The orange/black wire from the ECM harness seems to be in good condition as far as I can follow it

As long as there is NOT a P0381 error code there is nothing wrong with that wire. So since you've never mentioned that error code I would assume the ECM is damaged most likely from excessive AC noise from the alternator.

 

engine-3.jpg

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On 18/02/2018 at 9:27 PM, Mopar1973Man said:

That is correct. The ECM is in direct control of the lift pump. If the WTS light is delaying then the ECM is NOT booted up and ready. So the lift pump will not fire. The ECM must boot up first for the lift pump or the VP44 to fire. 

Yes I know that. You are the one who said to check the fuses and relays. Which ones then? 

On 18/02/2018 at 9:27 PM, Mopar1973Man said:

As long as there is NOT a P0381 error code there is nothing wrong with that wire. So since you've never mentioned that error code I would assume the ECM is damaged most likely from excessive AC noise from the alternator.

I got another ECM from a running truck same year etc and new alternator as stated and still thr same result.

Do I need to check the codes using a scanner? I have just been usin the key method. Only "cruise" comes up as I've stated the vaccum line has been disconnected

 

 

I am in the process of getting another ECM out of another running truck. Same year and trans.

Should it not work right away or does it need to be flashed in order to start working

 

Thanks again

Pete

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2 minutes ago, dripley said:

If it does not work on your truck I would go over everything you did and see if something did not get reconnected. It is possible you not knocked something ajar or loose while working on the truck.

 

Thats what I'm hoping to get out of this post. What else could be causing  this issue?

it seems it has to be the ECM or its wiring. Nothing else controls it

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