2010 sel 3.0L overheating kinda

[Slovette99]

So I'm getting right into it. My friend asked if I could do a coolant flush on her car. No problem. Well I then find out that it has been overheating really quick. So I drained the coolant and did a flush on the system making sure no plugs. I fill it with water and a bottle of prestone coolant system flush. Ran it for a while and noticed that it was normal temp. Thought ok that was easy. But then noticed that the lower hose was way colder than the upper. So I suspected maybe the water pump was out. It has 130k mike so it's possible.

I removed the water pump after the flush had run for a while. The pump was leaking a little through the weap hole and there was some black chunks hard chunks in the weap port. Caught it in time right! Well put in the new pump and filled with water to flush out the rest of the junk and coolant flush. Drained and filled with coolant. Ran great no overheating. Made sure to bleed off the air and drove no overheating.

Next day said that it's doing the same thing. So now I'm thinking maybe temp sensor is bad. Well I got one from autozone but for the life of me I can not find where it is. Nothing online about it. Fords website doesn't show one. So how the heck does this thing read coolant temp. I was a Ford tech for several years up to 2005 so this one has me stumped. Any help on other people having this issue or where the temp sensor is would be greatly appreciated. Sorry for being long winded.

[fusionmanor]

I looked it up at Ford parts, they don't use the term "coolant temp sensor" at all for a 3.0. It could be the "Intake manifold temp sensor" listed in Emission Controls > Sensors seen on a exploded view of a cylinder head.......? The 2.5 is in the cylinder head as well.

[Frank F]

What does OBD 2 port give you for temperature reading?

[drolds1]

Ford has been using cylinder head temp sensors instead of coolant temp sensors. IDK where it's located on this engine but since you have automotive mechanical expertise if you poke around the heads, you should be able to find it, especially if you have the replacement part to compare it to.

 

The black chunks are a bit concerning, though. Have the hoses ever been replaced? They could be deteriorating from the inside. Maybe this stuff has clogged up the radiator as well.

[Slovette99]

Thanks for the feedback. I have been swamped with work and haven't had a chance to work on it again. I will look for a sensor on the head. I'm just wondering where autozone got the part from lol. I don't have an obdII scanner anymore. For some reason I sold it after I had back issues thinking I would never get back into working on cars again. Stupid. I will look into the cylinder head temp sensor.

[Slovette99]

So after looking for ever I could not find the location of the temp sensor. I called a friend that still worked at the dealership and asked him if a tech would know where it is located. They pulled out a manual or looked it up on their end. It is directly under the throttle body on the side of the head closest to the firewall. To get to it I pulled the battery which didn't leave much room but was able to get in there to loosen it up. Once I broke it lose literally 1/8th of a turn it came out by my fingers turning it. I tested the ohms on the new part and they were around 45 and the old one I removed was at 15. Pretty contingent that it was the issue. We drove it after replacing the sensor and no overheating issues. Spread the word on where these things are because I played hell trying to find it. Thanks again for your help.