Edit: 5/21/16
Ran it hard (Short WOT sprints) and nothing, thump started on the short drive back home, this is what it sounds like and what the gauges were at.



Edit: new development as of 19:20 5/18

New development.

After I changed the (Fuel) filters I drove it around some unloaded, worked great, couldn't read data with my scanguage though because it decided to quit on me yesterday so I had the SCT flash device setup to Datalog so I can read the data when I can find a windows PC.

Talked to my dad and told him it was driving fine, he told em to go ahead and hook up to the trailer and tow it around some so i did, after about 8 miles I pulled over and heard the thumping from the intake (We had thought the dumping may have been the engine running lean with the restricted filter), so I towed the rig back home and let it sit for a little, and then decided to reflash to the stock tune to see if the thumping would happen.

After towing about 4 miles with the stock tune I lost throttle response for a few seconds, I decided I should turn around so I pulled into the turn lane just to have the truck idle down to ~500 RPM and then die. No CEL and it would just sit there and crank over.
I unplugged the ICP just to make sure and still no joy, so i towed the truck home and it will sit there until tomorrow afternoon when I get off work to test the FICM voltage.

I think it's either a computer or sensor issue, but any input is very much welcomed.




My dad has a 2005 F250 4x4 crew cab lariat, 6.0 auto trans.
What he's done so far:
SCT tune (The lightest one they offer)
EGR delete
4" turbo back exhaust
Cat delete

And we have a scanguage to monitor engine parameters.

So far we have had to replace these parts for various issues

Ficm (Got a rebuilt one, that's supposed to be built to better specs from a (Semi) local 6.0 mechanic)
HPOP
Injectors
ICP
IPR


A few weeks ago he was towing a tractor and trailer (~8K lbs) to a job and it faltered and died on him, wouldn't restart.
Took the truck home and started diagnosing and we weren't getting oil pressure to the ICP for it to start, replaced the ICP and we were good.

So he towed a D3 for a person (~15K loaded) and after about 15 minutes of towing he said he lost throttle response for a few seconds and the ICP and FICM voltage were fluctuating like crazy, he kept going after the throttle came back and didn't have any more issues.

I drove it the next evening to try to recreate the issue and couldn't, the only thing I saw that I don't understand is the MAP reading will drop from 28+PSI under acceleration to 0.0 or 0.1 PSI, but I keep boost on both the dash and digital gauge.

And then today I tried to tow the tractor/trailer about 15 miles and it was fine until everything warmed up, i lost throttle response a few times and when I pulled over I had a thumping from the airbox that increased with RPM and then went away over ~1800 RPM.

Dad told me today that he knows he going to have to replace the head gasket because a few months ago he noticed his Degas bottle was empty and he just left it alone because he didn't want to deal with it.

So I think the thumping is from the head gasket but I'm not sure about the MAP dropping off.

We will be using ARP studs but what gaskets should we go with?

 

OEM Ford is what I used. Got them from Ed at FICM.com. I heard that Anthony (run60run) is trying Felpro I think.

 

Read the post on 5/13/16. intake deep thump May help clear up your problem. You're on the right track

 

I have seen the MAP sensor reading drop to zero as well on a few different types of OBDII monitors when the boost goes over 28 psi. Not sure why this happens but try reading the MAP in voltage instead of PSI.

 

Thank you guys for the input.
Dad is currently working out of town so I'm not working on this too hard but after talking to a buddy who had a 6.0 for his work vehicle (County owned, he got to maintain it for the most part) he was thinking we had an air issue (maybe a clogged intercooler).

That got me thinking, if it's not air, which I don't think it is because of the boost we're making and unloaded power, it's fuel.
So I called my dad and asked when the last time the fuel filters were changed, his response "I don't know, sometime last year, probably 3 or 4 oil changes ago"
So I told him I would change the filters when I get a chance and see if it makes a difference, he says "Wait, there's more than one filter?"
So I think we may have a very full fuel filter on the frame rail and that's why we're having the issue after running hard with a load.

I still want to do a compression test though just to see the numbers.

 

So I got the fuel filters today, was gonna change them but it has rained all day (3.5 inches from ~3 when I got up to 2:00 when I got home) so i'm not in a hurry to get wet and nasty when I can wait until the weekend.

But I've been doing some research and I'm starting to compile a list that I would recommend my dad do if he plans on keeping the truck because we tow fairly heavy quite a bit, our 5th wheel camper weighs 12,500 semi-dry, our D3 weighs ~14K, we borrow a backhoe fairly often and it weighs very close to 16K, and then for little jobs he tows the tractor with bushhog and usually 100 gallons of diesel, so 8.5K for that.

I Stil plan on doing a compression test but here's the list so far.

Head studs and gasket
EGT probe install with Edge monitor
and Oil cooler flush and filter install.

Also he apparently hasn't maintained the trans in the 120K he's owned the truck, so I'm thinking we should drop the pan, change the in pan filter, clean the magnet, and also change the in line filter that's supposed to be changed ever 30(?)K.

Any possibility that doing any of that would cause issues?

 

Has the STC fitting been upgraded? You also need to catch up on all maintenance with OEM, only, filters.

 

Yes, when the mechanic replaced the HPOP he installed the updated version of the STC.

Another question (I know I'm full of them), does the 6.0 have a fuel/water separator drain like the 6.7's?

 

Yes it does.

 

The drain is on the HFCM on the frame rail drivers side right beside the front driveshaft. Allen key to open the old style one. Knurled **** if updated.

 

Ask away, you are are the right track with your maintenance.

Two things I would add to your list. An OBD monitor so you can keep an eye on the oil & coolant temps as well as the FICM health. Also the blue fuel spring upgrade - the injectors will thank you!

 

Thanks guys, changed the fuel filters today, secondary filter was a little brownish but the primary filter was black.
Put the tune back on (I returned to stock while diagnosing) after driving for a few miles and drove for another 20 miles or so, more power than before and no issues so far, gonna tow the tractor to my uncles house tomorrow to see if I can recreate the issues now.

Currently the truck is running the motorcraft gold coolant, should we change?

I told dad about the filter on the trans, he agreed we should change it, he said he was not aware of it so that is now on the schedule.

For the OBD monitor we're looking at a Edge insight CTS or insight CS with an EGT probe so we can monitor EGT's.

Now I've been reading some info about the oil coolers and how they can fail from the felt from the filter element.
Is the bulletproof diesel kit a good one? I see they have 3 different kits, i only looked at the "mid grade" one and it was pretty expensive ($1200).

I also want to pull a intercooler hose and see if the intercooler is oily.

 

The stock oil coolers are just fine if you keep up on the cooling system maintenance!
If you haven't order up some fumoto valves, vc9 and 45 gallons of distilled water. Read the tech folder and follow the coolant flush instructions.

Put in a new oil cooler, delete the EGR if you are not in a smog/EPA zone. Add a coolant filter and you should be fine.

Look at doing the blue spring upgrade. That makes a world of difference, It also ensures you do not drop fuel pressure at WOT.

 

Here is the link to the coolant flush.

https://www.ford-trucks.com/forums/1...tore-plus.html

 

Thank you for the info.
New development.

After I changed the filters I drove it around some unloaded, worked great, couldn't read data with my scanguage though because it decided to quit on me yesterday so I had the SCT flash device setup to Datalog so I can read the data when I can find a windows PC.

Talked to my dad and told him it was driving fine, he told em to go ahead and hook up to the trailer and tow it around some so i did, after about 8 miles I pulled over and heard the thumping from the intake (We had thought the dumping may have been the engine running lean with the restricted filter), so I towed the rig back home and let it sit for a little, and then decided to reflash to the stock tune to see if the thumping would happen.

After towing about 4 miles with the stock tune I lost throttle response for a few seconds, I decided I should turn around so I pulled into the turn lane just to have the truck idle down to ~500 RPM and then die. No CEL and it would just sit there and crank over.
I unplugged the ICP just to make sure and still no joy, so i towed the truck home and it will sit there until tomorrow afternoon when I get off work to test the FICM voltage.

I think it's either a computer or sensor issue, but any input is very much welcomed.