javatech@bellsouth.net

Help. The coolant overflown bottle om my T-Bird Keeps filling
up and the car starts to run hot. I beleive that the cooling fan
is not coming on at the proper heat range. What sensor should
I replace. The Engine Coolant Temperature sensor or the
Coolant temperature sending Unit. I beleive that the sending
unit controls the temperature guage on the dash but do not
know what signals the fan to come on. Any help would
be apperciated.

Thanks

Tom Adkins

javatech@bellsouth.net wrote:
> Help. The coolant overflown bottle om my T-Bird Keeps filling
> up and the car starts to run hot. I beleive that the cooling fan
> is not coming on at the proper heat range. What sensor should
> I replace. The Engine Coolant Temperature sensor or the
> Coolant temperature sending Unit. I beleive that the sending
> unit controls the temperature guage on the dash but do not
> know what signals the fan to come on. Any help would
> be apperciated.
>
> Thanks

The problem is likely not a sensor. The fan is controlled by the PCM.
Does the fan run? If not the suspects would be the fan motor or relay.
What year is the car and which engine?
Tom

javatek?@usa.com

Yes the fan runs. What is the PCM ? I have taken out the
thermostate and am running without it. So why would the
oveflow bottle fill up all the time. I still think that the fan
is not coming at the proper heat range. The radiator and
water pump are only 1 year old. So I don't know what the
problem is. The raditor cap is new as well. I thought that
the cap might not be the right pressure and letting the coolant
seep too soon. What is your thoughts.

>> Help. The coolant overflown bottle om my T-Bird Keeps filling
>> up and the car starts to run hot. I beleive that the cooling fan
>> is not coming on at the proper heat range. What sensor should
>> I replace. The Engine Coolant Temperature sensor or the
>> Coolant temperature sending Unit. I beleive that the sending
>> unit controls the temperature guage on the dash but do not
>> know what signals the fan to come on. Any help would
>> be apperciated.
>>
>> Thanks
>
> The problem is likely not a sensor. The fan is controlled by the PCM.
> Does the fan run? If not the suspects would be the fan motor or relay.
> What year is the car and which engine?
> Tom

pick one

If you run a koeo self test you'll know if the fans work or not because the fans
will either work or they wont. If there is a electrical problem with the fans
you will get codes. No codes go to the basics of cooling system diagnosis.
<javatech@bellsouth.net> wrote in message
news:t9te31d3tllqrrnduk92i2v209a39o2m5v@4ax.com...
> Help. The coolant overflown bottle om my T-Bird Keeps filling
> up and the car starts to run hot. I beleive that the cooling fan
> is not coming on at the proper heat range. What sensor should
> I replace. The Engine Coolant Temperature sensor or the
> Coolant temperature sending Unit. I beleive that the sending
> unit controls the temperature guage on the dash but do not
> know what signals the fan to come on. Any help would
> be apperciated.
>
> Thanks

Tom Adkins

javatek?@usa.com wrote:
> Yes the fan runs. What is the PCM ? I have taken out the
> thermostate and am running without it. So why would the
> oveflow bottle fill up all the time. I still think that the fan
> is not coming at the proper heat range. The radiator and
> water pump are only 1 year old. So I don't know what the
> problem is. The raditor cap is new as well. I thought that
> the cap might not be the right pressure and letting the coolant
> seep too soon. What is your thoughts.
>
>


The PCM is the Powertrain Control Module (main engine computer). It is unlikely that
the fan is coming on at the wrong temperature. The ECT (Engine Coolant Temperature)
sensor tells the PCM what the coolant temperature is. If it were out of range enough
to cause overheating (and excessive cooling system pressure) you would also have other
severe drivability concerns. You didn't state the engine size but I'm starting to
suspect it's a 3.8L.
Remove the radiator cap and top off the radiator. If you see bubbles with the engine
running the problem is most likely blown head gaskets. Look to see if you have bubbles
coming out of the radiator neck while it's running and check back.