I'm pretty sure I'm looking at Head Gaskets.
Overheating and puking out the degas lid when pulling a load up a grade.
Runs great otherwise(unloaded or loaded flat).

Just installed my pressure gauge on the cooling system and without a load it seems fine, never really goes over 6 PSI.

The weird thing is though, it runs at 0-1.5 PSI most of the time. This makes me think there is something else wrong like the cap isn't holding pressure at all(new cap same symptoms as old cap), or there is a leak somewhere else in the system? I would have thought the system would operate under some sort of pressure idling around under normal load? (cap mating surface looks good)

It does creep up to about 5 going up a good grade unloaded and right about that time the fan kicks in. Then after the hill it quickly drops back to 0.

Am I way off here? is 0 PSI at warm idle normal?

Also when it is overheating if I drop it down into 3rd to get the RPMS up around 3K it starts to cool back down. i'm wondering if this would be true if it were HGs since you would have higher pressures in 3RD?

I was tempted to pressure test the system right off the bat, but going by bismics guide that would be a bad idea due to danger of forcing coolant into the cylinders. So I'm going to be ordering a vacuum pump to do the vacuum test first.

I'm leaving to do my first load test with a good gauge installed tomorrow. Will post results when I return.

 

Doesn't sound normal to me. Mine starts at 0 cold and goes to ~6 at warm idle.

Check out the TSB 09-8-3 (link at top of the page). It deals with coolant loss and various tests to narrow it down between the cap, oil/egr coolers, HG.

Are you monitoring oil & coolant temperatures?

 

Also keep in mind that the Coolant bottle could be cracked and Venting the Pressure just Food for thought here


If it was me The Next thing I would check is the EGR Valve pull it and check for Coolant there and its EASY you didnt say anything yet about smoke so Odds Are it isnt the EGR Cooler

Whats Odd is Both/Either a Head Gasket issue or a Blown EGR Cooler issue would put pressure into the Coolant bottle This is why I mention a Cracked Coolant bottle


1. As mentioned ^^^^^^ Hows ECT vs EOT??????????

2. Any Smoke at all????????????????????

3. Iv also seen this same senereo with only a BAD Thermostat but since you only Puke/Overheat pulling IDK

4. this goes with the above alittle does ECT jump around get hot spike then drop

5. a plugged oil cooler can do this to

6. Is your EGR Valve Plugged in

7. Fan Clutch comes to mind here to can you see FAN RPM and also check the Fan wires right where they cross from engine to fan shroud

Im shure Bismic has all this in his writeup so what have you checked so far and do you have a Gauge and what gauge brand

 

That doesn't seem right, most guys have a puking issue when pulling hills. And the OEM cap vents/pukes at 16 psi. Which is quite a bit of pressure when you think about how little water compresses. Normally I'd say check a new degas cap and see if your puking goes away...it's a common cure for those that have had the issue; but I see you've already done that. Like Blade suggested, pull your EGR valve & check for coolant there. The '05 and up engines have been known to blow the EGR cooler when they're starved fro coolant from a clogged oil cooler. Something is getting warm since the PCM is spoiling the fan. If your light, you shouldn't need the fan to stay cool under the hood. Maybe the EOT/ECT delta is getting out of hand?I wonder if your leaking coolant/pressure at a heater hose, or one of the smaller hoses on top of the engine? There is one that comes around behind the turbo under the cowling (below the wiper blades)...not exactly sure where it comes from, but I'd check them all for white residue...assuming your running Ford Gold. Not sure what the other brands of coolant leave behind at a leak.Not exactly. Assuming your running a 5R110 (TorqueShift Automatic) the engine will work harder while in 6th than it will in 3rd. The two things changing when you drop from 6th to 3rd...lower cylinder pressure and higher RPM's. If you had a pyrometer plumbed into one of the exhaust manifolds you'd also notice the EGT drop like a rock at that lower gear.

 

Sorry for the lack of relevant info. I meant to add all that data.
~EOT Vs ECT: Between 8-12 depending on load
~Tried with EGR Cooler both plugged in and not. Didn't throw a CEL and didn't seem to change the temp at which the fan kicked in (was monitoring spreads when I tried it).
~EGR valve was dry
~Fan speed seems right. I think it would go up to 3500 RPMs when on and loaded. It's been a while since monitoring that one so the number may be off.
~EOT and ECT seem to stay fairly close and don't "jump" around but start to climb steadily as soon as i get to a good hill. They generally drop fairly quickly after the hill or if I shift down into 3rd.
~no smoke, except a small amount on cold start and the normal black smoke under hard acceleration.

a couple things I am wondering about is if there is a good way to tell if the water pump is operating within spec?
Maybe the previous owner had flashed the PCM with a more aggressive program? Can I tell with AE what version the computer has on it?

leaving this morning for Texas. Will be back with more results on Tuesday.

 

Ok Looks like it's definitely the HG's... I think.
I went ahead and replaced the degas cap(again). This one holds the pressure. Under load the pressure gets up to 16 and levels off. Under heavy load, pushing up a hill, it even goes over 16.

I'm getting mixed statements about weather a bad EGR cooler can pressurize the cooling system like that?

I have an EGR delete ordered and I guess I should go ahead and install it.

I'm considering just getting a $4500 rebuilt engine with ARPs instead of paying that much to do the HG and head work.

Only problem is I just moved to Indiana and don't have a shop to do the swap in. Back in AZ my friend owns a shop with a perfect cab lift.

I guess I need to find a good shop I can trust to do it right that won't charge me an arm and a leg.

 

EGR cooler can pressurize the cooling system like that. Cheezit ( I think) posted a video a few months ago on that subject. I think you will still get some coolant in the EGR passage in the intake.

 

The EGR cooler sees similar amounts of pressure as the cylinders, especially under boost conditions; the may not be as high...but they're high enough that a failed cooler can over pressurize the coolant system. I would assume EGR cooler failure before head gasket on this particular engine. I'm not saying the head gaskets never fail, it's just not a common issue. The EGR cooler on the other hand has been known to fail more often than the head gaskets. And depending on model ('03/'04 verses '05-'07) some are a little more fragile than others as far as how much abuse they'll take before they fail. As Rusty has eluded to, I would point the truck nose down and pull the EGR valve. If there is coolant (may look like oil when it mixes with soot) in the intake, your looking at a EGR cooler failure.

The device your calling the cooler that you plugged in/unplugged is the EGR valve. The cooler is under the right hand side of the engine's intake manifold (passenger side of the truck). You can't plug it in, it's plumbed into the truck. If your not aware, leave that valve plugged in at all times. If you don't the PCM won't spoil the radiator fan and the truck will overheat when your pulling a load.

If your delta is staying within 8-12 degrees of each other, I'd say your oil cooler is in good health.