Expedition keep over heating- please HELP!!!

[Jamied64]

Hello eveyone

There is some great people here willing to share- I have been in the shadows reading and reading many of the posts and I have learned very much. I am finally at the point where I need help!

I own a 2003 Expedition, Eddie Bauer 4x4 5.4 triton 190K

I have an overheating problem that is driving me crazy and I am looking for some information if someone else had this problem, or can chime in and help!!!

Around last September, on a short drive the engine temp gauge went o full HOT, dropped into limp mode and the reduced power light came on. Within maybe 10 seconds of this, sometimes little longer, the gauge would drop back to the middle operating temp and then NEVER again run hot until an overnight park and engine cool-down. I checked the coolant right away when I got home and noticed it was quite low so I filled it up. Since then I have the same issue
I learned that if I get under the truck and pump the rad hose a few times BEFORE it overheats, I can clear some air from in the coolant, with a bubble or two coming out, and then it wouldn't overheat at all. The engine never runs rough, no sign of leaking fluid but the coolant does drop over a long period of time and I do smell a feint burning smell from engine bay- not exhaust. Been like this since I bought it (only put 2K in mileage on it). Also the day I bought it I had it pressure tested and it passed no issues

Since all of this, I have barely driven it in fear of making things worse.
This problem eventually turned into the coolant being pushed out of rad cap under too much pressure, even with the cap off. I initally thought head gasket so I had my mechanic do the air test from the coolant degas/overflow where if there is combustion gas in there is changes color. He said it failed this test and he told me head gasket

I started doing my own research and work on the truck and I am not fully sure he is right. Here is what I have done to the truck to eliminate things

Changed accessory belt
Changed oil
Changed thermostat (OEM Motorcraft)
Changed ECTS (engine cooland temp sensor)
Fully flushed coolant sytem and added new coolant (green 50/50)
Pulled and checked water pump
Back flushed both heater cores
Two OEM overflow caps
Double checked heater core vacuum valve is functioning

Put it all back together- same issue

Next I did cylinder compression test- all above 165, highest was 185. Not one cylinder side by side had a number to worry about

Tried leak down test- couldn't get conclusive results so aborted
After reading a few posts about the intake manifold water jacket issues, I decided to pull mine and see if that was it. I 100% have a bad manifold heater jacket that needs repair, but could this cause all of the air getting in there?
The top of the intake to the coolant crossover was where the issue is- NOT bottom of the manifold to cylinder head

See pics

http://www.expeditionforum.com/attachment.php?attachmentid=10465&stc=1&d=1430533808

http://www.expeditionforum.com/attachment.php?attachmentid=10466&stc=1&d=1430533821

After further inspection, The rear driver side coolant jacket seemed to have a crack in it? Could just be a cast line- not sure.......

http://www.expeditionforum.com/attachment.php?attachmentid=10467&stc=1&d=1430533838



Do you guys think the Manifold issue, which is common, could cause this air problem?Could it suck air? Would that make it fail the coolant/air test?

I read on some forum that a guy had this issue and he figured that when the engine was cool, air would get in through that gasket and create a bublle or pocket in the coolant system


Any advice offered is much appreciated!! Thanks

 

[Jamied64]

Sorry, forgot to add that when it over heats, every single rad hose (upper, lower, and all heater lines are COLD- not even warm)

The coolant, even though under pressure, is warm, not hot

The oil is clean both in the valve cover and dipstick

I get bubbles occasionally but not on cold start up, or consistently


thanks

 

[69Hcode]

Might be water pump. I have heard of the vanes wearing out on mod motors. Make sure the fan is turning the right direction. Are you sure the thermostat isn't upside down? Not sure if its possible on our cars. Just throwing some ideas out there.

I did my water pump a few weeks ago because I had a credit at autozone that was gonna expire. My old one looked like new still. It was a real easy job since I have electric fans on.

 

[stamp11127]

You may be overlooking the cause. Since it failed the combustion gas test I would ask myself what are the paths for the gas to get into the coolant. Two come into my mind, head gasket and cracked head or block.
You may consider draining the coolant, removing the t-stat, filling with new coolant then checking for combustion gas again.
If it fails again there are a few heavy duty block additives used in big tracks that may allow you to get by for a while.
Please let us know what the outcome is regardless of what you decide to do.

 

[Jamied64]

thanks for the advice so far- I plan on changing the intake manifold to repair what I can see as two possible spots (both aT COOLANT CROSS OVERS) for coolant to leak out/air to get in

 

[wcm7823]

I had the exact same issues on my 03 expy. ..changed intake and it runs really good now but I'm chasing a bank 1 and 2 lean check engine light

 

[Skauber]

If you get lean code on both banks, it's either a major vacuum leak somewhere, which could include any seals in the intake after the MAF sensor but doubtful that it's intake gaskets. It's rare that both go bad at the same time. It could also be a crack early in the intake.

It could also be a dirty or bad MAF sensor. Try cleaning it, and see if it goes away. If you have a scan tool with live data on it, you could post your MAF values (in g/sec) on idle to see if it's within spec.

 

[Skauber]

And another thing I didn't have time to write earlier, fuel delivery. If it's starving for fuel, it may set of lean codes. This may include bad fuel pump (less likely) or clogged filter (more likely). If you have any other codes than lean codes, it may help pointing you in the right direction.