won't restart immediately after shutoff

motleycrew · Dec 20, 2013

HI guys,
Truck is an 06 King Ranch. Start it up cold, it runs rough for a few minutes then smooths out. Will hold 3500psi oil pressure under full load WOT. Once it's warm it will not restart. I'm talking like shut if off, then within 2 seconds try and fire it up, it won't do it. The engine barely stops and I try it again. NO GO. Builds less than 200lbs when cranking. Run it wide open 3500psi. Shut it off and immediatly restart - 150psi.

It won't build oil pressure at this time. Cools down, fires up and good to go, carrying the 3500 as long as you don't shut it down.

It has new injectors, ALL orings in the HP system are new. Upgraded standpipes and dummy plugs resealed.

I have tried multiple USED hpops and IPRs, all with the same result. I even just tried another old FICM after I got it hot. Confirm the no start, swapped FICMs, nothing.

I also have tried several oil filters. This oil filter stand is broken at the top, it does not have the bypass valve or whatever goes in the very top. Is this needed for my particular problem? The drainback in the bottom still functions. It will fill the oil filter housing within a couple seconds of cranking during this no start problem.

Airleak it hot, and you can hear a little hissing out at the pump, but I have heard that on every 6.0 I've worked on.

Can a bad HPOP still carry max pressure anytime, but cause a no start hot? I have never personally seen one that will hold max pressure, but cause a warm no start. And what's with the chuggle during a cold start until it warms up?

I have an extra confirmed bad pump. If anyone could point me in a direction of dissasembly of the HPOP itself, I would be grateful. Seems to be pressed togather....

thanks everyone,
mike

DEEZUZ · Dec 21, 2013

Well, with that bypass missing from the standpipe I've measured as low as 2 psi of low side pressure......

mint-6oh · Dec 21, 2013

What is your ipr at to maintain 3500psi? What is icp desired compared to actual while driving? Is the truck tuned or stock? The hpop system is capable of more than 3500psi. Where injectors stand pipes and dummy plugs all done to fix this problem?

motleycrew · Dec 23, 2013

hey guys,
ipr was about 70% while pushing 3500psi. ICP actual is close to desired, I have seen others be further apart and not have any issues.
The injectors are from power parts engineering, they were replaced for more power, I believe they are supposed to be like a 75hp injector.
The standpipes, dummy plugs were replaced for this problem. I kept doing air testing and would hear a leak here then fix it. Air test it again, hear another leak then fix it. So eventually just tore it completely down and replaced them all.

It has a SCT tune, but while diagnosing I am just running it on stock.

Snake · Dec 23, 2013

Fix your stand pipe, put a Motorcraft oil filter in, and cap things off with an OEM oil filter cap.

.

motleycrew · Dec 31, 2013

ok,
As an update...
I replaced the oil filter tube, the drainback valve in the bottom of the housing, new ford filter and cap.

Still doing the same thing, although I have some new info. I scanned it with AE this time, and here's what I am getting.

WOT run at about 50 mph pulling a hill. Calling for 3528.14psi, I am only at 2766.89 actual. The IPR is at 85% at 3.61volts.

My information before was wrong, I made several test runs and am getting the same thing. Can't get IPC up to within a couple hundred of desired. Immediatly after shutoff, no restart, builds about 300psi. Give it just a whiff of ether, it fires, runs rough for a couple seconds, then your good to go.

Pump?

suprdzlduty · Jan 1, 2014

what kind of oil are you running and what is your oil temp after you run it. if you have a oil cooler plugged up your oil temp could be through the roof...seen that cause a no start before...

buschpoweredstroker · Jan 1, 2014

I would look into the LP pump, one of ours had almost identical issues and that is where we found the issue.

motleycrew · Jan 2, 2014

suprdzlduty said:
what kind of oil are you running and what is your oil temp after you run it. if you have a oil cooler plugged up your oil temp could be through the roof...seen that cause a no start before...

Didn't look at the cooler temps but the oil cooler is brand new. I put a new ford piece in when I did the injectors about 100 miles ago.

IF the low pressure was the problem, wouldn't I have other symptoms? It seems like a low pressure supply problem "to me", but not a actual LP pump. More like a loss of prime or something.

I dunno. The fact that you can run it, and if you weren't watching actual HP with a scanner, you wouldn't think that there is anything wrong. It runs down the road perfectly fine.

You can shut if off, then even before the turbo stops, try to restart and it won't. Crank until the batteries are dead. :shrug:

Snake · Jan 2, 2014

Exactly how my truck with a high pressure oil leak ran. Perfect, until it was hot, shut down, and restarted. Or at least try to restart.

.

buschpoweredstroker · Jan 4, 2014

Our 04 had no other issues other than the hot start problem. We started with a new HPOP and oil cooler, then checked for leaks(backwards I know) and found none.We had been running synthetic oil and then switched to a heavier non synthetic and the problem almost disappeared but not quite. We then took the truck to Strictly Fords and they have the problem diagnosed as the LPOP, it is only running single digit pressure I believe, and the truck still runs fine even on a hot tune. Still waiting to get the truck in the shop to repair- good luck

Big Angry Hillbilly · Jan 4, 2014

Air check the HP system. I know you said all the **** is new, but check it again anyhow with air or nitrogen.

When it won't start, try unplugging the ICP sensor, as well.

suprdzlduty · Jan 5, 2014

When you try to restart it when hot, does the oil pressure gauge come up? If it is possibly a lpop issue, it could be the regulator, the spring can get weak and or get stuck, causing a lack of proper pressure to the hpop system...

motleycrew · Jan 9, 2014

update on this:

Air test the system, I have a slight hiss out of the hpop hole. Even when i close the ipr all the way, I still have a very slight hiss. Everything else is sealed up tight. I have heard this on many other 6.0's I've tested, so I don't know if it means anything or not.
I put a mechanical gauge on the Oil Filter resivoir and here are some numbers:

120 psi at startup, about -5*
70 psi about 10 min. later
20-70 psi operating temperatures

maybe 7-10 psi while cranking hot after a shutdown and no restart.

motleycrew · Jan 9, 2014

Ran it the other night, it broke down again on the road. It had been running for about 30 minutes. Started to chug and stumble like it had air in the system, then cleared up and took off again. Came to a stoplight, went to take off and NO power. Lots of white smoke and missing bad, finally died and wouldn't restart.

Ficm voltage stayed up, I didn't have the low pressure gauge visible at the time. I also was not able to see the HPOP pressure at the time. Got it back to the shop and had cam/crank position sensor codes along with the normal 2 glow plug codes. I would guess the cam/crank codes were from missing so badly, I have seen that before.

I did notice that the fuel pump seemed to sound a little different, almost struggling when you KeyOn. Maybe it's just because it was so cold. I don't attribute any of the problems to cold weather though, since it's been having this issue for a couple months now.

johnp115 · Jan 9, 2014

Have you fixed your standpipes dummy plugs and most importantly the STC fitting update? I just had the same exact problem as you.

motleycrew · Jan 11, 2014

johnp115 said:
Have you fixed your standpipes dummy plugs and most importantly the STC fitting update? I just had the same exact problem as you.

Hi,
I replaced all standpipes with the updated ones, dumy plugs and stc are all new and good.
thanks

motleycrew · Jan 14, 2014

more info:

If you are sitting there idling, put it in gear, then goose the throttle, the rpms come up normally then they will drop back down and die. If you slowly bring the rpm up and slowly back down, it is fine.
It will also die alot if you just shift it into a gear from park. It can sit there and idle all day, then shift it into drive and it will shut off. Just like you shut the key off. NOT like the converter is locking and causing it to stall out.
If you try and brake tourqe it, bringing the rpms up to say 1000, it will start to surge between 750 and 1250. I don't know what icp is doing, I didn't have it hooked up, I will check.

It is still doing the immediate no start thing though after you shut it off..

suprdzlduty · Jan 16, 2014

Have you checked fuel pressure?

04cr450 · Jan 19, 2014

If you do the air test again, while you have air pumping thru the system take the oil cap off and listen.. if you hear hissing coming out of the oil filter housing u have a bad hpop, 99% sure. Try it. Also while doing this test make sure the ipr is energized