Tro Sampson
Member
Good Evening Expo family! How many temperature coolant sensors are there on an 04 Exp. XLT 4.6L and where are they located?
Temperature Coolant Sensors
- Thread starter Tro Sampson
- Start date
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TomB985
Well-Known Member
There's no coolant temperature sensor, they use a cylinder head temperature sensor to infer coolant temp. Location is in the attached diagram.
Tro Sampson
Member
Thanks TomB895!!! Second question.... Is there only one CHT sensor on 04 Expedition or two? I changed out one but just want to confirm that it is just one?
Also, recently had CHT sensor (geniune Ford part) and theromstat changed, radiator flushed, new plugs and boots (Motorcraft) and new air filter installed but gas mileage is still terrible. Truck is not running hot, P0128 code is gone.
Filled up yesterday and only got 86 miles out of a half tank of gas. I was sitting in my driveway with A/C running for about 5-10 minutes waiting on my wife and son to come out and I noticed the gas hand had already started to move from Full in less than 5 miles of driving and just sitting there idling. Not sure what is going on (MAF sensor, O2 sensor???)???
TomB985
Well-Known Member
The shop manual was a little confusing on that, as there is a reference to one on the passenger side had as well. But the wiring diagrams only show a single sensor, which I believe to be accurate.
is the tool you're using to read codes capable of reading live data? What are your short- and long-term fuel trims looking like?
Tro Sampson
Member
Thanks for your replies...
I just filled up and after 140 miles I’m down to a quarter tank of gas. It’s pretty bad right now. I’m not getting any codes or service lights now.
I’m going to clean the MAF sensors next and see what that does.
Any tips on improving gas mileage?
Tro Sampson
Member
Cleaned the MAFs and seems like mileage has gotten worse. Filled up this morning and got 30 miles out of a quarter of a tank.
After about 3-5 miles of driving, the gas hand is already moving. I’m going to do another code scan to see what I get.
Following things done in past 3 weeks:
New plugs and boots
New CHT sensor
Radiator flush
Installed high performance air filter
Cleaned MAF
Not idling rough but not completely smooth either. Not blowing smoke out exhaust.
Don’t want to got changing O2 sensor just to troubleshoot issue unless I know it’s to be changed. Starting to run out of ideas.
After about 3-5 miles of driving, the gas hand is already moving. I’m going to do another code scan to see what I get.
Following things done in past 3 weeks:
New plugs and boots
New CHT sensor
Radiator flush
Installed high performance air filter
Cleaned MAF
Not idling rough but not completely smooth either. Not blowing smoke out exhaust.
Don’t want to got changing O2 sensor just to troubleshoot issue unless I know it’s to be changed. Starting to run out of ideas.
TomB985
Well-Known Member
Yep, my first suggestion was to go back to my previous post and record your fuel trims. 
Seriously though, without more information we don't know if everything is running correctly or not. Can you describe your driving conditions a little better? Do you live city driving, or is this on the highway?
Seriously though, without more information we don't know if everything is running correctly or not. Can you describe your driving conditions a little better? Do you live city driving, or is this on the highway?
Yep, my first suggestion was to go back to my previous post and record your fuel trims.
Seriously though, without more information we don't know if everything is running correctly or not. Can you describe your driving conditions a little better? Do you live city driving, or is this on the highway?
Couldn't agree more on fuel trims. You can figure out why you're getting bad gas mileage by just observing the stats and behavior of fuel trim. If you can give us that information, including how the fuel trims behave under high RPMs, we can help put you in a good direction.
Tro Sampson
Member
Thank You Very Much for your replies. I will get my truck scanned again to get those trims so that I have that info for you.
Also, I live in a metro-suburban area around D.C. So I experience both city and highway driving. So it's a combination of both. I live about 20 miles from Annapolis, Maryland so when I go there it's highway driving out on a highway route (3-4 four lanes with 65 MPH speed limit). Went to Annapolis the other night for a school event and the mileage was not very good just for a 20 mile trip. Wasn't pushing more than 65 to whole 20 miles because I was trying to pay attention to the gas hand.
But what's interesting is that when I filled up Wednesday morning, the gas hand had already started moving after driving only 3-5 miles at residential speed limits of 30-35 MPH. I live about 1.5 to 2.0 miles from the gas station and another 2-3 miles from my job.
I have a feeling that once I get the trims back, my Big Gurl is running rich. Hopefully the scan will bring me back a code other than P0128 and something more definitive including the trims. If the P0128 comes back that means there is another CHT sensor somewhere on my truck.
Just replaced the one right under the alternator on the engine block. My guy checked for a second one and could not find it. There is not alot of information out there as to whether there is one CHT or two on a 04 Expedition.
As soon as I get that information I will post it. Thanks again!!
Also, I live in a metro-suburban area around D.C. So I experience both city and highway driving. So it's a combination of both. I live about 20 miles from Annapolis, Maryland so when I go there it's highway driving out on a highway route (3-4 four lanes with 65 MPH speed limit). Went to Annapolis the other night for a school event and the mileage was not very good just for a 20 mile trip. Wasn't pushing more than 65 to whole 20 miles because I was trying to pay attention to the gas hand.
But what's interesting is that when I filled up Wednesday morning, the gas hand had already started moving after driving only 3-5 miles at residential speed limits of 30-35 MPH. I live about 1.5 to 2.0 miles from the gas station and another 2-3 miles from my job.
I have a feeling that once I get the trims back, my Big Gurl is running rich. Hopefully the scan will bring me back a code other than P0128 and something more definitive including the trims. If the P0128 comes back that means there is another CHT sensor somewhere on my truck.
Just replaced the one right under the alternator on the engine block. My guy checked for a second one and could not find it. There is not alot of information out there as to whether there is one CHT or two on a 04 Expedition.
As soon as I get that information I will post it. Thanks again!!
Tro Sampson
Member
Here are the Trims:
PARKED AND REVVED AT 2500RPM
MAF FLOW GR/SE 60.24
ST FTRM1 % -3.4
LT FTRM1 % 6.2
ST FTRM2 % -1.0
LT FTRM2 %. 1.5
DRIVING AT 40MPH
ST FTRM1 % -2.2
LT FTRM1 % 3.1
ST FTRM2 % -2.2
LT FTRM2 %. 1.7
PARKED (NO REV)
O2S11 V 0.070
ST FTRM11 % 0.7
02S12 V 0.775
02S21 V 0.785
ST FTRM21 % -3.4
I think it might be the 02 sensor but I could be wrong. The engine runs fine and I got codes from the code reader.
PARKED AND REVVED AT 2500RPM
MAF FLOW GR/SE 60.24
ST FTRM1 % -3.4
LT FTRM1 % 6.2
ST FTRM2 % -1.0
LT FTRM2 %. 1.5
DRIVING AT 40MPH
ST FTRM1 % -2.2
LT FTRM1 % 3.1
ST FTRM2 % -2.2
LT FTRM2 %. 1.7
PARKED (NO REV)
O2S11 V 0.070
ST FTRM11 % 0.7
02S12 V 0.775
02S21 V 0.785
ST FTRM21 % -3.4
I think it might be the 02 sensor but I could be wrong. The engine runs fine and I got codes from the code reader.
