a friend of mine has a 98 f150 supercab 4.6 and his truck over heated today and he has a trouble code p1299 cylinder head over temp protection active. the code has been cleared but returns. he says hes not leaking antifreeze but he is loosing it. thats why he over heated.hes checked his oil its not in there hes at a loss as to whats going on. he said the truck is running fine otherwise. any ideas as to what this code means or as to whats going on thanks fo any help in advance

 

I would pull the dip stick and look for water in the oil.

 

i told him to do that right away he said he did but nothing. he said its not leaking on the ground or anywhere but i mean its got to be where else can it be going.......unless. he was complaining about his heater core and he kept calling me because he couldnt find it but i never heard anything more about it . is it a possibility its leaking under the dash and under the rug? although i would assume he would see the rug wet? i dont know im stumped i guess ill have to go take a look myself.

 

If the heater core is leaking inside he would smell it. Has he checked for excessive white smoke out the exhaust. Also open the radiator cap when engine is cooled off and look for steady bubbles in the tank. Another thought is to pull spark plugs and look for wetness.

 

as far as bubbles are you refering to excessive air in the system. and the smoke would be the truck burning the antifreeze. thanks torkum

 

Yes, these would be signs of a intake leak or head gasket leaking.

 

ok well i talk to my friend again and i know get the real story ok well he has had issues with his heat just going out his blower is still working but no hot air. well one day it just started working again he had heat so he left well enough alone. yesterday it just over heated. he said he had coolant all over his motor. no that he was low on coolant just that it was all over his motor. and now he has no heat again. any ideas? im thinking bad thermostat. clogged system?