BAD RONALD
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Has the coolant level dropped more than once? If you are losing coolant there's a crack or leak someplace.
Coolant sensor/ possible cooling issue/code P1299
- Thread starter bar422
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Has the coolant level dropped more than once? If you are losing coolant there's a crack or leak someplace.
I haven't noticed any coolant level drop before I put more in yesterday but I know it hasn't dropped since then and I checked it twice. I'm going to plan on changing the thermostat and replacing the coolant again. Any more input will be appreciated!
Just checked the coolant level after adding some yesterday and it is where it should be after sitting all night.......that probably eliminates the idea of a possible leak. I'll take anymore input on this....Thanks!
FordandPolaris
Full Access Members
Some leaks only open up when they are under pressure. Check it again after driving some and then letting the truck cool to truly eliminate the possibility of a leak.
Did a water pump and thermostat on it today.......my local Ford shop said they have seen the water pump rust and fall apart on the inside so I decided to get the thermostat done on too. The water pump looked good when it came off but put the new one on anyway.....when the thermostat was removed it was found to be stuck open.....I'm thinking this is the culprit. New thermostat was installed and new Yellow Motorcraft gold coolant. I'll run it a few days and see how it goes. Thanks for all the responses!
B
bedrck46
Guest
Thanks for the update
stamp11127
Full Access Members
A stuck t-stat doesn't cause your original problem. It is just a flow restrictor when cold.
BAD RONALD
Full Access Members
...under pressure and hot. Esp if the missing coolant is disappearing out of the tailpipe. A fairly long test drive is in order.
I don't think that there ever was coolant missing (Although I'm still not completely sure it was put back at the correct level in the first place after the system flush)....after I checked the level initially and added some the correct level hasn't changed. A longer drive to test it out is planned for the weekend. Hopefully with the new sensor, water pump, thermostat and coolant this problem has been cured.....if not....I'm not sure what 's next.
I thought about the coolant going out the exhaust too or other head gasket related things but haven't found anything pointing to that......no coolant in the oil or no sweet smell in the exhaust either. I was also told that if the truck is cold and you take the cap off the coolant tank and have someone turn it over while watching the tank to see if there is a bunch of back pressure would indicate a head gasket as well......it didn't do that either. A compression test hasn't been done though.......I would think there would be other issues if the gasket was the case. I appreciate the responses so far and welcome anymore input.
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