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Discussion Starter · #1 ·
My 1995 F250 7.3 with only 104,000 miles has been running great even though I only use it once a month. It always starts in a couple of seconds. It has new batteries and a great starter that kicks it over very fast.

Two weeks ago I took a trip in it to get a trailerload of hay. It ran great there and back. I stopped in the barn unloaded the hay, restarted it and parked it in the shed. Today I went to start it and it only kicks over. No putts, no smoke.

I opened the valve to bleed the fuel bowl and kicked it over a second with the valve open and fuel shot out of the valve making me think the fuel pump is working ok.

What is the first thing I should check on it?
 

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Are you getting any warning lights when you first turn the key on such as the wait to start light?

Do you see any tach movement when it is turning over? More than just a little bit of movement.
 

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Are you getting any warning lights when you first turn the key on such as the wait to start light?

Do you see any tach movement when it is turning over? More than just a little bit of movement.
This is important. If you are not seeing the WTS light come on and then go off like normal, your PCM is not powering up. This could be from a variety of things, but we can cross that bridge if we get there. Check on that and report back.
 

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Discussion Starter · #4 ·
I had my dash removed a couple of years ago for repairs and the Wait To Start light never worked after that. I did not bring my truck back to get that fixed because I did not think it was necessary.

I will check my tach tomorrow.
 

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Are you getting any of the other lights when you first turn the key on?

Also check the fuses in the under hood fuse box, #22 and #9 for sure. Don't just look at them but test them with a meter.

Power Distribution Box
 

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When you first turn the key to RUN, look VERY closely at the Check Engine light. It should blink, but it's VERY brief, like 1/10 second or less. That will also tell you whether the PCM is energizing.

Do you hear the GPR click when you turn the key to RUN?

Q&D fuse 22 / PCM power test - PULL fuse #22, turn the key to RUN and leave it there, then go back under the hood and put fuse #22 back in. Since you're under the hood, you should hear the GPR click very clearly. If you don't, that suggests a PCM power problem.
 

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Discussion Starter · #7 ·
When I turn my key to run, the check engine light blinks on and then off very fast one time, the ABS light comes on for about 2 seconds then goes off. I hear a click. I put the #22 fuse in while the switch is on run and I hear a click. I checked the #9 fuse.

When I kick the engine over it goes fast enough that my oil pressure gauge goes to normal and the tach goes to about 200 rpms.

I am very grateful that all of you are helping me with this problem.
 

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OK, now on to some other things. You mentioned that you are not getting any smoke out of the tailpipe so this is saying that you don't have any fuel getting to them or the injectors are not firing.

Take a pencil type air pressure gauge and wrap a rag around it and while someone is cranking the engine over check the pressure on the same valve that you depressed on the filter housing to get fuel out of and get back to us on how much fuel pressure there is. Also you can try switching tanks just in case there is a problem with one tank.
 

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^^^ Those are all good signs; PCM is powering up, sufficient lube oil pressure to feed the HP reservoir, sufficient crank RPM. Good signs for working components, but bad for finding the smoking gun. Other than the fuel checks mentioned by bugman (oh - what's the fuel level in each tank?), you're pretty-much at the point where you'll need a compatible diagnostic device, to do tests like an injector buzz test, and check some live data points while cranking. Well, some other "observational" tests remain - disconnect and remove the IDM, and give it a shake, and listen for (yes) sloshing water. Common issue; rain gets into it from the hood seam, and shorts it out. Also, check the valve cover connectors for damage. If any are, remove the valve cover and check the associated connectors/wiring underneath.
 

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Discussion Starter · #10 ·
OK, now on to some other things. You mentioned that you are not getting any smoke out of the tailpipe so this is saying that you don't have any fuel getting to them or the injectors are not firing.

Take a pencil type air pressure gauge and wrap a rag around it and while someone is cranking the engine over check the pressure on the same valve that you depressed on the filter housing to get fuel out of and get back to us on how much fuel pressure there is. Also you can try switching tanks just in case there is a problem with one tank.
I put the gauge on the valve that looks like a tire valve (I assume there is only one like that) and while it was cranking over only a little diesel escaped and the gauge measured no pressure. What does this mean?
 

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This is pointing towards the fuel supply or pump.

Have you pulled the filter to see how much fuel is in the bowl?

How much fuel do you have in your tanks? Is it above 1/4 in each and have you tried switching tanks?
If it is below 1/4 on the gauge put 5 gallons into one of them and then try again. The fuel pickup foot may of broken off.

I'll be gone for the next 4 days but I am sure that others will jump in to help some more.
 

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Discussion Starter · #12 ·
One tank is 3/4 full and the other is 1/4 full. I removed my fuel filter and the fuel was about halfway up the bowl. The filter was probably taking up the rest of the room.

I cranked the engine a few times and the bowl filled up 3/4 of the way. I changed tanks and cranked a few more times and the bowl filled up all the way. I put the filter back in forcing much of the fuel to spill into my valley.

I tried starting again. Still no luck, no putts, no smoke.
 

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^^^ Okay, this confirms the first stage of the fuel pump (that fills the bowl) is working, and you're getting delivery from the tanks. But it's a two-stage pump, and the second stage (that consumes the fuel in the bowl) could be what's inop. The lack of pressure at the schrader valve suggests that.
 

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Discussion Starter · #14 ·
I replaced my fuel pump about 10 years ago when it started leaking. It was a difficult job so when it started leaking again 2 years ago I brought it to a shop and I think they put on a rebuilt pump. It sure should have lasted longer if that is what it is. It was a very expensive job.

What else can I check before I change the fuel pump?
 

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I have had fuel pumps that have only lasted as long as it took to install them and I have had them last a few years, you never know.

As for what else you can check, about the only thing that you can do is to get a actual fuel pressure gauge and plumb it into the filter housing to give you a actual reading. But things are pointing to the high pressure side of the fuel pump.
 

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Had a similar problem in our 95 turned out to be a bad wire under fuze block under hood. Pretty easy to pull mounting and turn block over wire will stand out if bad. Took 12 hours in shop to find it. Try fully charging the batterys and than jumping with another truck at the same time. I have had a starter the sounded and tested good cause too much draw.
DENNY
 

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Sounds like you're having the same problem as I am, im replacing the 2 stage on Monday, as well as all the lines and so on. Keep throwing money at it??
 

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Discussion Starter · #19 ·
I put on a new fuel pump. Still nothing. I tried to check the pressure at the schrader valve with my air gauge but it does not fit well and fuel leaks out but I get no reading on my gauge. How many psi should the gauge read? It doesn't seem like it has much pressure.

When I was changing the fuel pump I noticed that the screen between the bowl and the fuel pressure regulator looked completely stopped up. I cleaned it and put it back. I checked the oil in my HPOP and it was full and about as dirty as my oil is when I change it.

Do you have to bleed anything when you change the pump? Last time I changed it I did not bleed anything. The bowl filled with fuel fairly quickly.

What really puzzles me is that the truck ran so well last time I used it and it broke in the 2 weeks it was not used. If it was a gas engine I would think a rat or squirrel ate some wires and check that first. I park it under a shed so it should not have gotten rained on while it was parked.

I don't know what to check next????????
 
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