07 4.6 cooling/overheating issues - UPDATED

[Shoktronic]

Ok I am stumped & need some input.

Here is the rundown. 2007 Explorer, 2wd, 4.6 w/110k location Vegas / South Carolina. Had a leak from the heater hose / rear air manifold. Had it replaced 12/2018. Coils were also replaced & injectors serviced at that time. We had the fan constant on/off issue for over a year after we had the coils replaced (non OEM). Fan clutch was replaced by the shop but same issue persisted (again non OEM). We drove around with this since I couldn't find a solution. No overheating issues "that we noticed".

September 2019 being fed up with noise I replaced the water pump, fan clutch, thermostat, radiator cap, pulleys, tensioner & belt (All OEM). No change to the fan noise, no cooling issues "that we noticed"

I finally found the thread here & swapped the coils back to Motorcraft ones & it fixed it! Fan only came on under heavy loads, AC... The normal stuff. This was done just before we moved from Vegas to South Carolina (02/2021).

So... We have been here for a little while did some grocery runs, nothing too far. The car was transported, not driven BTW. Had to pick some things up about 75 miles from the house or about an hour drive. Noticed the fan kick on a little more than normal but no lights or temp fluctuating. On the drive back home shortly after we arrived here I had to speed up a bit after exiting a shopping center (goosed it). Almost immediately after getting off the accelerator I smelled coolant & saw steam out the right fender. Popped the hood and the top heater hose was split along the top 8" to 10". So had a shop repair it.

Now I'm having issues of the fan coming on a lot which has me concerned. Duh out my OBDII to check the temps using Torque Pro. OBDII says 220-230, dummy gauge no change. Fan kicking on at 210 - 215, loss of power on side streets when temps jump. Had the local shop run the gambit on tests & nothing. No head gasket leaks, oil is clean, coolant is clean, no CO2, pressure test was fine & No air in the system.

So I'm not sure what to check or replace. It does appear the heater core may be plugged as it's not "hot" but only warm. Rear air is an oven. If it's plugged I'm not sure if the radiator might be plugged? I haven't done the temp check yet on the hoses. My infared gauge gets in tomorrow.

It's a new area so I don't know how "good" the repair shop actually is.

I know cars & can turn a wrench but cooling systems ain't my forte.

Any input / suggestions would be GREATLY APPRECIATED!

If you need any other details just ask. I've tried to be thorough, albeit long winded.

Thanks

 

[Shoktronic]

Ok I am stumped & need some input.

Here is the rundown. 2007 Explorer, 2wd, 4.6 w/110k location Vegas / South Carolina. Had a leak from the heater hose / rear air manifold. Had it replaced 12/2018. Coils were also replaced & injectors serviced at that time. We had the fan constant on/off issue for over a year after we had the coils replaced (non OEM). Fan clutch was replaced by the shop but same issue persisted (again non OEM). We drove around with this since I couldn't find a solution. No overheating issues "that we noticed".

September 2019 being fed up with noise I replaced the water pump, fan clutch, thermostat, radiator cap, pulleys, tensioner & belt (All OEM). No change to the fan noise, no cooling issues "that we noticed"

I finally found the thread here & swapped the coils back to Motorcraft ones & it fixed it! Fan only came on under heavy loads, AC... The normal stuff. This was done just before we moved from Vegas to South Carolina (02/2021).

So... We have been here for a little while did some grocery runs, nothing too far. The car was transported, not driven BTW. Had to pick some things up about 75 miles from the house or about an hour drive. Noticed the fan kick on a little more than normal but no lights or temp fluctuating. On the drive back home shortly after we arrived here I had to speed up a bit after exiting a shopping center (goosed it). Almost immediately after getting off the accelerator I smelled coolant & saw steam out the right fender. Popped the hood and the top heater hose was split along the top 8" to 10". So had a shop repair it.

Now I'm having issues of the fan coming on a lot which has me concerned. Duh out my OBDII to check the temps using Torque Pro. OBDII says 220-230, dummy gauge no change. Fan kicking on at 210 - 215, loss of power on side streets when temps jump. Had the local shop run the gambit on tests & nothing. No head gasket leaks, oil is clean, coolant is clean, no CO2, pressure test was fine & No air in the system.

So I'm not sure what to check or replace. It does appear the heater core may be plugged as it's not "hot" but only warm. Rear air is an oven. If it's plugged I'm not sure if the radiator might be plugged? I haven't done the temp check yet on the hoses. My infared gauge gets in tomorrow.

It's a new area so I don't know how "good" the repair shop actually is.

I know cars & can turn a wrench but cooling systems ain't my forte.

Any input / suggestions would be GREATLY APPRECIATED!

If you need any other details just ask. I've tried to be thorough, albeit long winded.

Thanks

And I read the other threads but some never followed up. The one that they changed the cap on the radiator seemed too different.

And I remembered the old shop did the whole fluid swap AND a radiator flush sometime after the coils were changed.

 

[boominXplorer]

Coolant condition? Mucky at all? Have you changed thermostat or radiator? You might have a blockage in either.

 

[Shoktronic]

Coolant condition? Mucky at all? Have you changed thermostat or radiator? You might have a blockage in either.

Coolant is new because of the heater hose blowout. Thermostat was changed in 09/19 with a Gates 180 deg. The coolant overflow has a kinda mucky foam residue towards the top. It's dry & crusty so not sure from when. I'll take a pic shortly

 

[Shoktronic]

Ok... So I got the infared temp gun out after a run to the store. Here's what I found.

Torque / OBDII - 215
Upper hose - 155
Lower hose - 133
Thermostat housing - 161
Top of radiator - 158
Radiator cap - 105
Intake - 115
Heater hose - 168/170

So it looks like the sensor is failing & needs replacement. I'm thinking I'll have it done along with the radiator & bypass the heater core for now. I'm guessing the radiator is partially plugged if the core is plugged.

Feel free to give input if you see something different being a remedy.

If anyone has input on a decent radiator other that oem let me know too!

 

[Blackhawkxx]

If anyone has input on a decent radiator other that oem let me know too!

There are a lot of threads on radiators here if you do a quick search. I preferred the O.E.M. because I think they are the best and the Explorer rad isn't the easiest to change.

 

[Shoktronic]

There are a lot of threads on radiators here if you do a quick search. I preferred the O.E.M. because they are not the easiest to install.

Was that sarcasm or a typo? LOL

 

[Blackhawkxx]

Was that sarcasm or a typo? LOL

Proofing reading does help. Thanks, it is edited.

 

[Shoktronic]

Proofing reading does help. Thanks, it is edited.

No worries!

After reading I'm thinking of going the all aluminum route but I'm reading there's issues with the trans lines. We had the radiator replaced in the first 4 years twice by Ford for the side cracks. I really don't want to go thru that again.

 

[Blackhawkxx]

No worries!

After reading I'm thinking of going the all aluminum route but I'm reading there's issues with the trans lines. We had the radiator replaced in the first 4 years twice by Ford for the side cracks. I really don't want to go thru that again.

Use the Ford 16 lb radiator cap. It removes a lot of stress. Many on here has done so including myself without any negative effects.

 

[94Eddie]

If anyone has input on a decent radiator other that oem let me know too!

I used the radiator linked below along with a 16 psi radiator cap and replaced the transmission lineconnectors with Dorman double O-ring parts. It appears the radiator I linked is no longer available. I strongly suggest using the 16 psi cap over the 20 psi factory cap. IMO, the 20 psi operating pressure causes many unnecessary failures in the cooling system. I have been running the 16 psi cap for months with zero issues. After this summer I will know for sure if running a 16 psi cap works as well as a 20 psi cap. A 20% drop in system pressure has a big positive affect in the stress level the cooling system has to deal with. The 20 psi cooling system pressure could very likely have a lot to do with the all to common radiator failures 4th gen Explorers experience.

https://www.amazon.com/gp/product/B00YWCZLO2/?tag=serious-20
https://www.amazon.com/gp/product/B0025P29KM/?tag=serious-20
https://www.amazon.com/gp/product/B000C5HRYK/?tag=serious-20

 

[Shoktronic]

Use the Ford 16 lb radiator cap. It removes a lot of stress. Many on here has done so including myself without any negative effects.

I can't seem to find the 16, only 20s come up on all the parts sites. Is it for a different year or engine size? And searching on a mobile phone on this site is horrendous! It's not very user friendly with all the ads, etc.

 

[94Eddie]

I can't seem to find the 16, only 20s come up on all the parts sites. Is it for a different year or engine size? And searching on a mobile phone on this site is horrendous! It's not very user friendly with all the ads, etc.

Here you go:

https://www.amazon.com/gp/product/B000C5HRYK/?tag=serious-20

It is a Motorcraft RS76 radiator cap.

 

[Shoktronic]

This is getting to be very odd now. So looking things up the coolant temp is now a "CHT - Cylinder Head Temp" sensor. OK, got it. I checked on its replacement and its under the intake. Bit of a pain but no big deal. Saw it was located between the middle two cylinders. So, I decided to take a temp reading there and on the opposite side....

Torque 220F
Driver side - cyl 6&7 160F
Pass side - cyl 2&3 195/198F!!!

So WTF? Im guessing it is reading 220 since it sits more inside.

So what would be causing high temps on one head and not the other?

Could a sticking or bad injector cause it? Lean condition maybe?

Clogged water jacket?

Im about to loose my mind chasing this!

 

[Shoktronic]

Well anyone choosing to follow along I believe 95% I have found the problem.

After speaking to one of my neighbors who is an old time ford mechanic (who knew, just moved here!) he gave me some insight that led me down the rabbit hole.

When I mentioned one head was hotter than the other he said "you got a leak". When he elaborated he said it's whats possibly causing my "Bank 01/02 Lean" codes. Said that, if I have a bad intake gasket or crack, air will get in and lean it out. When it gets lean it gets HOT fast. He also said "plastic don't move in the same direction every time it gets hot, it's a gremlin". LOL. The 'ol boy was onto something there!

So I searched knowing that and came across several folks on other forums "F150 & Chevy" talking about that SAME scenario.

So it looks like I may have either a warped or cracked intake like so many other Explorer owners.

It completely explains the temps, codes, coolant & gas smell from time to time and why everything has been so erratic!

So now it's time to hunt down the last model of the Ford OEM intake 9L3Z-9424-G.

Just for good measure I'm swapping the CHT (cylinder head temp sensor) & thermostat while I'm there along with the heater control valve.

Wish me luck folks! I'll post pics & updates when I find something or finish!!

 

[Blackhawkxx]

So it looks like I may have either a warped or cracked intake like so many other Explorer owners.

Did you try spraying starting fluid around the intake when it is running to see if the idle speed changes?

 

[Shoktronic]

I was going to try it tomorrow. My neighbor said to try it. Said it might work, might not. Depends on if it's moving when its hot or how the crack opens up. It's never the same which is why Ive gone crazy. Sometimes super hot, sometimes a little hot.

 

[Shoktronic]

I am happy to say our little Explorer is out of the OR and doing well. In fact I don't think it has EVER ran this well in 6 years or more!

So here is the rundown of everything replaced.

Radiator cap (15 lbs - Ford OEM) (Thanks @94Eddie )
CHT Sensor (Cylinder head temp aka "Coolant temp sensor")
Injectors (Ford OEM)
Intake manifold (9L3Z-9424-G)(*** Note: This is the "updated" model. If you swap to it you will need shorter bolts! Goes from M6x63mm to M6x45mm. 10 needed. Get them from hardware store 8.8 grade. Ford is overpriced!)
Back flushed heater & radiator using air assisted tool (https://www.amazon.com/gp/product/B000F5ECRW/?tag=serious-20)
New 195 Thermostat & gasket (Fail safe)

I also drained the capacitors to the ECU and allowed the car to relearn everything afterwards.

I honestly think this was multiple things after seeing that the injectors were not actually changed by the previous mechanic! They looked horrible! That was probably adding to the lean condition causing the heat up in the cylinders near the CHT sensor.

So I hope some of this information helps someone else down the road. If not, it's just a story of an adventure of another Ford owner!

Take care all!

 

[94Eddie]

Thanks for the update. I am sure it will help many others over time.

 

[Explorer_PL]

Thanks Shocktronic -
Valuable for me since I am chasing a gas smell under the hood and one side is running leaner so I'll start with intake gaskets.