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Discussion Starter #1
Hello,

I have a 2001 F-650 with the 5.9 Cummins.

Ever since it was 2 yrs old, I have had problems.

It has had (4) VP-44's

At least 7 lift pumps

All within 77,000 miles.

Over the last 4 years it has been to 4 different repair shops, including Cummins Power Systems in MD multiple times.

well, now it's gotten worse.

For the 1st 10 minutes the truck runs good. Then, after 10 minutes when the truck reaches 1800 RPM's the throttle gets erratic and loses power.

the truck bucks and nearly throws you through the windshield.

A few weeks ago the local repair shop replaced the lift pump. It ran GREAT for about a week.

Then it got real bad.

This week the truck repair shop has replaced:

- the lift pump again
- VP-44
- some sensors
-a fuel check valve on the back of the engine

and they checked all the wires for breaks, etc.

And the truck still isn't running right.

Could it be the ECM unit????

Has anyone seen this problem with the 2001 F-650's??
 

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'Ol Builder guy
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That's pathetic that they've replaced so many parts and not solved the problem.

Have the fuel lines been replaced?
 

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Discussion Starter #3
Duke said:
That's pathetic that they've replaced so many parts and not solved the problem.

Have the fuel lines been replaced?


no, the lines have not been replaced. It has crossed my mind that maybe there is a pinhole somewhere.
 

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Cam sensor? Ive seen a few go bad without throwing codes and doing what your explaining. Odd since that it fixed for a while after they put a new lift pump on it. How does the inside of your tanks look? Engine grounds? Since it only does it when its warmed up id guess cam sensor the one in the hole behind the air compressor.
 

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Discussion Starter #5
dieselboy740 said:
Cam sensor? Ive seen a few go bad without throwing codes and doing what your explaining. Odd since that it fixed for a while after they put a new lift pump on it. How does the inside of your tanks look? Engine grounds? Since it only does it when its warmed up id guess cam sensor the one in the hole behind the air compressor.

Dieselboy -

It's pretty aggrevating.

The local truck repair facility tested all the sensors.

They told me that the Cam Sensor was bouncing the needle all over the place. So they say they replaced it. But - after alledgedly replacing - the problem is still there.

But see, they did not bill me for ANY of the work done - which is why I used the word "alledgedly". So I have no idea what exactly they did.

They also told me that there is a check valve behind the block(?) that has never been replaced. they said that Cummins recommends that the check valve be replaced each time the VP-44 is replaced. I believe they cleaned it.

I am not sure about the engine grounds. They say they checked all the wires.

So at that point they were at a loss.

They called some engineer at Cummins and talked some technical stuff. The service advisor told me one of the pumps (I'm mnot sure which one) is putting out 25 pounds of pressure. He told me that the engineer said that 25#'s is too much and it should be 15 pounds. So the engineer told them to check the RETURN LINE for a blockage. I dropped the truck off and needed it the next day (as they already had it for an extended period of time). The advisor told me they disconnected the return line and the problem still existed. But I'm wonderin if they got busy and didn't have time to actually check the return line.

When I went to pick the truck up the advisor slapped the keys down on the counter and said "here you go sir", and turned and started to walk away. I politely and cheerfully said "do you have any more ideas?". He replied "I didn't build the truck, I can't fix the truck", and walked away. No offering me an explanation of what they tried, what they did, etc. He didn't even mention me paying them for their time.

About 4 veteran diesel mechanics have mentioned the possiblity that it could be a bad fuel line.

Today I spoke with Cummins Power Systems outside of Baltimore (huge cummins facility), and the service advisor told me that they have had a few Fords with defective fuel lines and some with bad fuel tanks.

When they replaced the VP-44 it did run better - but the problem is still there.

And when it is cold, it runs GREAT for the 1st ten minutes. Which is odd, cause if it is a fuel problem, then I don't think a cold engine or a warm engine would make a difference.

My truck doesn't have an air compressor (it has hydraulic brakes). Where is the Cam Sensor? I wanna look at it and see if it looks new.

Thanks for any help you can give!
 

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26 tires rolling
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DVS said:
They called some engineer at Cummins and talked some technical stuff. The service advisor told me one of the pumps (I'm mnot sure which one) is putting out 25 pounds of pressure. He told me that the engineer said that 25#'s is too much and it should be 15 pounds. So the engineer told them to check the RETURN LINE for a blockage.

Thanks for any help you can give!
Sounds like a lift pump is what they were talking about. lift pump failures are the main reason for VP44 failures.


I would find a different diesel mechanic. sounds like yours has a major case of "we could care less" maybe I would try to make an appointment at the Cummins shop.
 

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Powered By Ford
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sounds like a major case of the SBS issue, SBS meaning Shoulda Been Sold LOL sorry, just trying to make you laugh, good luck with finding a fix.
 

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the only fords that i know of having the in tank line issues are the older body style. The 01' shouldn't have many in tank issues. The problems that i have seen are on the dual tank trucks is at the balance valve if its not a switchable system.
You might have a bad throttle position sensor too but that normally causes a check eng light.
I had a truck that would run fine when it was cold and when it warmed up it wouldn't boost up at all, changed the boost sensor and it was better.
Since your tach is jumping id still say cam sensor.
Look at the drivers side of the engine, if you have a air compressor there will be a gap above it to the injection pump. The sensor is screwed into the front cover in that hole. You should have one the 8.3l has 2.
Your truck might also be equipped with a engine speed sensor on the transmission bell housing. The ecm will sill use the cam sensor and they run the tach off the bell housing speed sensor.
 

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Discussion Starter #9
Dieseboy -

thanks for the info.

My truck does NOT have an air compressor. Can you tell me where I can find my Cam Sensor? I assume it's still on the driver's side? But where?

I have replaced the throttle position sensor.

I really want to zero in on the Cam Sensor, the truck runs fantastic when it is cold. And runs bad when it's warm. If it was a fuel line problem - it would run the same, cold or warm.

I'm thinking when I took the truck to the truck repair facility - I had two problems, but didn't know it. I'm thinking the VP-44 really was bad, as it runs 93% better. But also we have another component that is mal-functioning, and the repair facility did not put enough thought into it to realize it. I got a new, remanufactured VP-44 and to this day - they have not billed me, nor called me to tell me they want money.

If you could tell me where my Cam Sensor is, I would GREATLY appreciate it! Again, I do not have an air compressor.

Thanks,

DVS
 

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drivers side under the fuel pump the hole is where your ij pump goes
 

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Does this truck have an in tank fuel pump As well? We ran into a Grumond Van that had issues simular to this !ended up there was an electric fuel pump tucked up under the frame causing greif! Worth a look!!
 

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Discussion Starter #12
Dieselboy, I apologze for the delay in thanking you for the help and for the picture.

I did get a new cam position sensor - but we been so busy lately, that I have not put it on yet. I'll let you know what the outcome is.

Thank you for your help!


- DVS
 

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Discussion Starter #13
Well.....it wasn't the Cam sensor.

So I took it to the Cummins shop, and for $752 they connected a laptop to the truck, connected some fuel pressure gauges, and ran it on the dyno.

It ran flawlessly.

Wanna know why I think it ran flawlessly?

Welp, because they connected the pressure gauges to the fuel lines - they had to open a line. Everytime the fuel system is opened - it runs great for a few days afterwards.

So here is my new theory:

I am thinking there is dirt in the fuel tank, and it is blocking the fuel flow. I have heard that Ford has had problems with peeled paint and other foreign debris in their tanks.

I am thinking that when they open the fuel lines, the pressure releases and the dirt falls down. We are in a hilly area, so with the hills and turns - the fuel is sloshing around and any foreign debris is workin its way into the line.

Since the Cummins place runs the truck on the dyno - no fuel is sloshing, thus the problem is not duplicated.

I have been told that Ford has had problems with the sock on their sending units - where some have deteriorated.

I believe the tanks need a good flushing and the sending units need inspected.


Also - today the truck started running really bad. All it would do is idle. So I looked at the lift pump and I discovered that the Cummins facility left their furel pressure test line connected to the return line. I also discovered that fuel was leaking at the fitting on their test line. Would that little fuel leak make the truck only run at an idle?? It was too late in the day when I made this discovery - so tomorrow am I will have finish the job that Cummins charged me $752 for.

Any thoughts on my dirty fuel tank / line theory?

Would that small leak in the test line of the return line make the truck not run?


Thanks!
 
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