Cooling system brand new 03 3.9 Gen 2, Overheating still

Ant3.9LS03

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Looking for some suggestions. Cooling system is brand new on my 03 3.9 Gen 2, both radiator hoses, radiator, thermostat, housing assembly, all gaskets, 94n99, hose under intake manifold, water pump, degas with new hoses, aux pump, dccv and both hoses from dccv to upper hose and aux to thermostat.... I'm still running way hotter than the car should, my Temps stay around 212 214 then eventually rise to 223 225, I've used airlift kit on my car to 25 psi no air leaks, refilled completely airless, tried to bleed after with no air, and car is still running these temps, at this point idk what to do, what is my problem here? My fan kicks on fine from what I can tell. Turning the heater on makes temps fly down. Anyone with any advice to point me in the right direction would be the best help at this point, I'm left with changing my CHT sensor? Or am I stuck with a faulty thermostat? Bad fan? Another sensor I'm not aware of? Thanks guys... This is beyond frustrating as I just want to drive this damn car already... At this point I have money for the man who saves me from this nightmare if possible! And noting I'm ready to buy a cht sensor and new thermostat if this is poissbly my problem...
 
All OEM parts, I hope. People have had trouble with the aftermarket thermostat assemblies. I've also found some variation with the Motorcraft ones. You might want to try another thermostat. Also be careful when assembling it. Follow the manual. It is easy to damage it by pushing too hard on the wrong part trying to assemble and lock it in.

2006 Lincoln LS Workshop Manual
 
Ya I have all oem parts, and I will be trying a new thermostat to see if that's the issue then. I'm going to buy it from Ford parts giant this time, I believe the first one was from rock auto
 
My car was empty of coolant for a few months do you think any sensor like coolant temp sensor by oil filter could go bad? Or cylinder head temp sensor? Just wondering since it was empty of coolant for a bit while I procrastinated on the overhaul
 
All OEM parts, I hope. People have had trouble with the aftermarket thermostat assemblies. I've also found some variation with the Motorcraft ones. You might want to try another thermostat. Also be careful when assembling it. Follow the manual. It is easy to damage it by pushing too hard on the wrong part trying to assemble and lock it in.

2006 Lincoln LS Workshop Manual
@joegr I have the workshop manual and followed it to the T and also the threads on cooling system replacement. My only other question is I'm in California where the temp outside today is 103°F... Would this mean my Ls should still be running at 190-205 range? Or is there room for higher Temps because of my climate? Thank you..
 
Personally, I feel like 200 to 215 is okay. My LS runs hotter than my other cars, with the exception of the BMW that I had (it was about the same).
I would think that the coolant temp sensor would be okay. The CHT sensor does not contact coolant, so it wouldn't matter if the coolant was out or in. Do note that it is a one-time sensor. If you remove it, you have to replace it. It is distorted on install, and counts on this to make good thermal contact.
 
Personally, I feel like 200 to 215 is okay. My LS runs hotter than my other cars, with the exception of the BMW that I had (it was about the same).
I would think that the coolant temp sensor would be okay. The CHT sensor does not contact coolant, so it wouldn't matter if the coolant was out or in. Do note that it is a one-time sensor. If you remove it, you have to replace it. It is distorted on install, and counts on this to make good thermal contact.
OK sounds good I appreciate you and your knowledge with all this! I just did a little driving test and believe it or not the car was running at a steady 205 203 the whole time but my ac was never turned off, turned the ac off and kept driving and the car jumped up to 217 and never cooled back down? (106 outside right now) So now I know ac keeps my car Temps cooler and turning the heat on does the same? Would this be an indication of anything at all? I'm almost convinced now that my fan or something electrically telling my fan to turn on isn't working or doing its job correctly?
 
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OK sounds good I appreciate you and your knowledge with all this! I just did a little driving test and believe it or not the car was running at a steady 205 203 the whole time but my ac was never turned off, turned the ac off and kept driving and the car jumped up to 217 and never cooled back down? (106 outside right now) So now I know ac keeps my car Temps cooler and turning the heat on does the same? Would this be an indication of anything at all? I'm almost convinced now that my fan or something electrically telling my fan to turn in isn't working or doing its job correctly?
You should probably get FORSCAN so you can see what your variable fan percentage FWIW ...I didnt hear you say that the water pump was replaced ...the Existing MotorCraft water pump has plastic propellers...these can corrode inside and get wedged ...always good to get a water pump that has the metal propellers ...have you flushed out the system with distilled water a couple times and then air pressure bleed the system? I had a Snap-on bleeder perform the procedure by a professional shop ...my LSE doesnt fo past 96 Celsius with AC blasting and temps outside at 100 degrees...
 
OK sounds good I appreciate you and your knowledge with all this! I just did a little driving test and believe it or not the car was running at a steady 205 203 the whole time but my ac was never turned off, turned the ac off and kept driving and the car jumped up to 217 and never cooled back down? (106 outside right now) So now I know ac keeps my car Temps cooler and turning the heat on does the same? Would this be an indication of anything at all? I'm almost convinced now that my fan or something electrically telling my fan to turn in isn't working or doing its job correctly?
With my ac on or heater apparently Temps stay in the 190 to 205 range, the minute I turn either one off, my Temps slowly but surely climb up eventually getting to the 220 range with no fluctuation of going down?
You should probably get FORSCAN so you can see what your variable fan percentage FWIW ...I didnt hear you say that the water pump was replaced ...the Existing MotorCraft water pump has plastic propellers...these can corrode inside and get wedged ...always good to get a water pump that has the metal propellers ...have you flushed out the system with distilled water a couple times and then air pressure bleed the system? I had a Snap-on bleeder perform the procedure by a professional shop ...my LSE doesnt fo past 96 Celsius with AC blasting and temps outside at 100 degrees...
Sorry I have replaced water pump also, propellers on mine weren't gone from the original one but the surround base was corroded away. I have semi flushed the system by draining it for the 5th time now... I haven't filled with distilled water I have refilled with Motorcraft gold prwdiluted and used my air lift kit and pulled air from the system to 25psi and then filled airless.. So FORSCAN is only available via computer? Or can I get a scanner plug in that supports it? I have a nice scanner that shows live data... Also my car doesn't go past 205 at all with ac on.... Turn the heater on my car cools way down 196 area, and pretty quickly, both ac and heater off and my car will eventually get up to 214 then up to 217 and hit 220 area with no signs of it going down on its own with heater on or even ac.. I'm lost at this point and about to give up idk what to do or what can be my issue, I have pulled my intake manifold off 3 times now and thinking about redoing my thermostst junction area with a new thermostat to see if the plastic was faulty lol I'm lost
 
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@AmsterDutch my car doesn't go past 96 Celcius with ac on and it was 106 out today.. But ac off it runs hotter sitting around 214 F then 217 F then eventually 220 and I even got it to 225 226 idling revving at 2k rpms in driveway. Also this is after I used my airlift kit and had cooling system down to 25psi then refilled with no air.
 
@AmsterDutch do you know what your temps are when ac is off and driving?
I should be more technical ..When going up steep hills at 70mph with AC turned on and when I have the AC off my temps can reach 99 Celsius =110 Fahrenheit but they quickly go down to 93-96 Celsius when the terrain levels out...your situation is a little boggling to say the very least...I'm going to have to research this a bit more ...and I didn't mean run the car with distilled water just flush it out...you are correct to use a 50-50 diluted solution...I have always used green but I know some ppl who live or die by the GOLD Motorcraft...If I was a betting man ...which I'm NOT! lol I would say you could have a air pocket somewhere...Did you boil the Thermo in hot water to visual see it's opening before you put it in the car? There is a obvious connection with the heating and Air conditioning here that allows the antifreeze to cool down the Head temp....This would be what you should focus on and try to figure out what components are connected to this situation ...you can get Forscan Lite app on smartphone or download the Forscan program for free on a laptop ...a ELM327 adapter is best suited for the laptop and bluetooth adapter works well for Smartphone...does your scanner show both OBDII Coolant Temp and Cylinder Head Temp?
 
@AmsterDutch my car doesn't go past 96 Celcius with ac on and it was 106 out today.. But ac off it runs hotter sitting around 214 F then 217 F then eventually 220 and I even got it to 225 226 idling revving at 2k rpms in driveway. Also this is after I used my airlift kit and had cooling system down to 25psi then refilled with no air.

Normalish. The fan is not aggressive at all in cooling the engine. This is for gas mileage and for emissions. With the AC on, the fan has to move more air to keep the AC working well. A consequence of this is that the engine gets over-cooled a bit. Personally, I never have turned my AC off, and I don't know why anyone would. It stays on auto at 73 most of the time. Rarely, I may vary it between 70 and 76, depending on what I just did before getting in...
 
It stays on auto at 73 most of the time.
I heard you say this in a couple other threads and I now leave my AC on pretty much all the time also....even when I don't want the air coming directly out of the vents I will switch it over to defrost ...you and a few others on the forum agree it's good for the AC to keep moving and is actually better for all the AC components...
 
Normalish. The fan is not aggressive at all in cooling the engine. This is for gas mileage and for emissions. With the AC on, the fan has to move more air to keep the AC working well. A consequence of this is that the engine gets over-cooled a bit. Personally, I never have turned my AC off, and I don't know why anyone would. It stays on auto at 73 most of the time. Rarely, I may vary it between 70 and 76, depending on what I just did before getting in...
So you're saying this all sounds normal @joegr? I am just going off of what people swear by and that's the Temps running from 190 - 205? I was just very concerned that my car isn't cooling itself down properly without ac or heater on? With both off my Temps will never stay below 214? I don't mind running ac all the time and heater at this point to keep it cool, i will still change out the thermostat if that could be an issue, and possibly try and bleed more which I've done a million times lol. One thing I do notice is a whistle noise when ac and heater are both off, turn one or the other on and the whistling I hear under the hood goes away? Does this sound familiar at all?
 
I should be more technical ..When going up steep hills at 70mph with AC turned on and when I have the AC off my temps can reach 99 Celsius =110 Fahrenheit but they quickly go down to 93-96 Celsius when the terrain levels out...your situation is a little boggling to say the very least...I'm going to have to research this a bit more ...and I didn't mean run the car with distilled water just flush it out...you are correct to use a 50-50 diluted solution...I have always used green but I know some ppl who live or die by the GOLD Motorcraft...If I was a betting man ...which I'm NOT! lol I would say you could have a air pocket somewhere...Did you boil the Thermo in hot water to visual see it's opening before you put it in the car? There is a obvious connection with the heating and Air conditioning here that allows the antifreeze to cool down the Head temp....This would be what you should focus on and try to figure out what components are connected to this situation ...you can get Forscan Lite app on smartphone or download the Forscan program for free on a laptop ...a ELM327 adapter is best suited for the laptop and bluetooth adapter works well for Smartphone...does your scanner show both OBDII Coolant Temp and Cylinder Head Temp?
I didn't boil the thermostat.. Maybe I should get another to test it out. I got it brand new though and all Motorcraft when I swapped literally everything over. My whole cooling system is new besides the three hoses to the passenger side that go to dccv and aux pump. Also I don't think it shows cylinder head temp, it's only showing me ect on my scanner.. Not sure if that's the one by oil filter or where this reading is coming from
 
Your AC clutch may be making the noise when it is disengaged. It would mean that the air gap is a little too small, but nothing to worry about.
 
@joegr again I really appreciate your input on my issues it means a lot as I am lost, so to break this down for me, is it abnormal or normal that my car wants to run hotter with both heater and ac off? Do you think I am having an issue here or am I chasing down a problem that doesn't exist here? I'm just going off of what everyone says 190-205 (anything higher is overheating) it's runs these Temps just with heater or ac on, with them off a lot higher... In the end do you think I am having a cooling issue here or am I crazy. Thanks again..
 
When I've hit my engine and some of the smaller hoses on the top of the engine... with a temp gun... the readout is typically between 215-220F.

That seems to be the "happy" spot for an LS with a properly functioning cooling system. Especially in summer weather.
 
Yes, normal for a lower temp when the AC and/or heat is on.
AFAIK, 220 is a safe temperature. The last time I looked (years ago), mine was running around 200 to 210 (AC always on). The thermostats aren't prefect. Some are a little on the cool side, and some are a little on the hot side. Note that some cars now have electronically controlled thermostats, to reduce the variation.
 

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