No start and no power to the fuel pump, help!

[Doubt Incarnate]

excersizing connectors is as simple as dis-connecting and re-connecting them several times, letting the contacts drag over each other giving them a more or less fresher spot to work through. as far as testing, we already know it wants to start the motor, just has a problem with "run". checking for spark during start won't get us an answer. you'd have to take somewhere like advance, autozone they have a machine, or just look up how to check one with a multimeter, usually involves checking resistances.

 

[mikesparky]

cool, I'll look into that tomorrow. Thanks for the info.

 

[Doubt Incarnate]

it happens im off tommorow, so i'll probly check in online throughout the day. i did a quick search and found a thread about a no start problem fixed simply by cleaning the connections. it would be sweet if that worked out for you, but at the same time suck since you sunk plenty of cash in the soulution as well.

 

[Doubt Incarnate]

nothing new?

 

[mikesparky]

Sorry, yea it's been a busy day. I've started looking at car loans since I have to leave town for work in a week and am thinking this isn't going to be resolved soon. I'm heading out now to look at the connections and cross my fingers.

 

[Doubt Incarnate]

yeah i know how that goes. i ran around all day and accomplished about... nothing.

 

[mikesparky]

Running!

So I go out to do more diagnostics and just for the hell of it plug in my rigged wire from the 12v outlet to the fuel pump and REALLY hear the pump, no mistaking it. I freeze and unplug it, the noise goes away and I'm happy. I plug it back in, hear it again, hop in the seat turn the key and she starts right up! My only explanation is that all of the testing ran the battery down a bit and after a day's rest it had enough to get the pump going...? Whatever the reason, the immediate problem is resolved! Now I have to decide whether to have the transmission I ordered before all this started installed, or to sell both and cut my losses. I can barely get it into gear right now. Any opinions? (I love this truck, just need something reliable.)

P.S. I'll summarize everything later tonight in the hopes that it will help someone else in the same position. Also, I did not come up with connecting the pump to the 12v outlet. I'll try to hunt down the thread that gave me the idea.

 

[Doubt Incarnate]

i wonder if the pump sucked in some sediment. at least its running, as far as the transmission goes you can disconnect the lines at the cooler to see if its pumping, assuming it has enough fluid. if its weak maybe a filter change is needed, or worse but we'll stay optimistic. could be the epc solinoid in the valve body, which isnt that bad.

 

[mikesparky]

Dunno about the pump. I have a manual transmission and it's been going for a while so this isn't unexpected. With any luck I'll have it changed out tomorrow.

 

[Doubt Incarnate]

awesome

 

[mikesparky]

Not Running AGAIN

Well, it drove fine Thursday night and come Friday morning it wouldn't start again. I'm out of town but feel free to leave any suggestions!

 

[skoal_mint]

I think its the PCM, check the ground on it or get a used one.

as for the crank senor, usually when their bad you will never be about get spark, but i have seen some do other wise.

lastweek a guy blew his motor, we rebuild it and when we started it, it was missing like a *******, we replaced the MAF, and check a bunch of other crap and still nothing.. then we did some "thinking while drinking" and decided to change the crank sensor befor pulling the engine back out and it worked...turned out that broken connecting rod scraped it somehow

 

[mikesparky]

Thanks Skoal Mint. I'll check the ground and if that's ok I'll clean the crank sensor. Any suggestions on how to clean it?

 

[skoal_mint]

I really dont know a whole bunch on explorers, even tho i have one I am usually working with bigger trucks or rusted POS buick cars which iv been replacing pcms left and right

But the pcm gets it ground from the frame its bolts to..some pcms corrode very bad and you loose your ground their

 

[mikesparky]

I'm confused. I attached the pump to the 12v outlet and it didn't turn on. I checked with a meter and am getting a little over 12v at the pump. The wierd thing is the fuse in the 12v plug burnt out. I changed it and it burnt out again. Do you guys think this is a low amp problem from a short somewhere slowly draining the battery or a bad wiring in the pump or freaking santa claus? I was also thinking alternator since I had the truck running for an evening but now nothing. When the engine was running the battery gauge needle only went up half way. With the key on now I get maybe a quarter of the way up, prob less. Part of the problem or side effect? Still turns over strongly.

 

[budwich]

Yes you are confused... actually confusing... when you attached the 12 volt outlet to your pump... you attached one wire right????. what about the ground side?????? IIRC, you did your "quick splice" work on the connector at the pump... hmmmmmmm!! you need to check your work with a meter both in terms of voltage and continuity... without do "good" checks, you will continue to "spin your wheels" on this problem.

 

[mikesparky]

Haha, not meaning to spread the confusion! Not enough sleep I guess.
I connected the ground wire to the frame and it worked last time around. I was attempting to recreate the now miraculous start from last thursday and to convince myself that there is enough power to run the pump.

How do I test a ground for continuity? I've tested for voltage at the fuse block, inertia switch and pump and it was all the same. I still have to test for a ground signal at the fuel pump relay (I was out of town and a rain delay last night). I'm going to try cleaning the pcm grounds and if that doesn't work swapping it out and see if that helps.

 

[budwich]

It is more on a "test of continuity" in general..... go to inertia switch and disconnect / unplug / take it from the circuit. Measure your resistance of the circuit going towards the pump (PK/BK wire to ground). There should be some resistance. If there is nothing (high resistance), you have no connection along the way to the pump OR to ground. IF it is 0, you have short before / or at the pump. IF there is "some resistance", then you can run a jumper to this "test point", and the pump should run for as long as it is connected. That's the check. I know that you have done this before is "some form"... however, your testing has been "all over the place" and you need to go back to a more methodical route along the circuit path as opposed to jumping around at things... ie. alternator, fuel filter, regulator, etc.

 

[mikesparky]

a quick update

I jumpered at the relay and got a little over 12v at the pump (same as at the relay) which I believe tells me that the wiring to the pump is sound. So now I've got to look at the pump. I got the replacement at advance and have heard of these pumps failing quickly, but had no idea it would be this fast! If there was a surge in voltage would that cause a pump to fail prematurely?

*Thanks budwich, I did this test before I read your posting. I agree that my posts were a little jumpy. I had been going methodically from point to point not posting every step, and just posting when I had an idea or question.

 

[budwich]

I don't think you actually are doing the test that I suggested.... checking for voltage is just one of the tests. You need to do the continuity test that I suggested otherwise to quote a "famous" friend of mine... "You have done nothing!". In addition, the continuity test will tell something about the condition of your pump without having to drop your tank and stuff.

IF you did the test that I suggested... what was the resistance reading???