P1299 code
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P1299 code
My truck threw a code p1299 last night on my way home from the lake. I was towing on a huge grade and all the sudden my engine temp gauge pegged out on me and check engine light came on. I pulled over and noticed a bunch of coolant had overflown the cap but the engine didn't seem to have over heated. When I restarted the truck the engine temp was imidiatly normal range. I drove for another 30 min or so and the engine temp started to climb and then come back to normal then climb and stay pegged. I pulled over again and noticed the coolant level was low and coolant had overflown the resivoir. I restarted the truck and once again it was normal. I just drove surface streets the rest of the way with no issue. I suspect blown head gasket. 
Any ideas would be appreciated.
This is a 2003 F-250 6.8L with 100000 miles. Thanks
Any ideas would be appreciated. This is a 2003 F-250 6.8L with 100000 miles. Thanks
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Guessing can get you into a lot of trouble. Check for coolant in the oil if you suspect a head gasket failure. Also check for oil in the coolant. There are a lot of things that are more likely than a blown head gasket, i.e. a stuck thermostat, a faulty water pump, cooling fan, clogged radiator, etc. Do some logical testing and think it through before jumping to conclusions that it is a faulty head gasket.
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Thanks for the reply. There is not any water in the oil nor oil in the coolant. I just talked to a mechanic and he said it doesn't sound like a head gasket. I think I was just preparing myself for the worse.
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I was actually about 5 miles past the grade going down when the gauge all the sudden pegged. Going up it did not move at all. I did top off and cleared the code this morning. Now when I start it up. I can drive about 2 miles and the temp gauge will slowly start climbing up. If I hammer the throttle it will go down. I can also let it just sit at idle with the ac on and the gauge doesn't even move.
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When you turn the AC on, the cooling fan is always automatically turned on no matter what temp the engine is at. When the AC is not on, different sensors, coolant temp, determine when to turn the cooling fan on. That would be a good place to start. See if the radiator cooling fan is on, without the AC, when the engine is fully warmed up.
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2001 Ford F-250 5.4L p1299 code
I have been getting the same code p1299, I have changed the Cylinder head tempature sensor, thermostat, flushed the radiator, changed the wiring harness going to the thermostat, and the computer, and I'm still having the same code up. Is there anyone else who has been having this problem on a 5.4 motor and have fixed it. The dealership had it for two months and couldn't figure it out just seeing if anyone else has had any luck.. Thanks
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I have been getting the same code p1299, I have changed the Cylinder head tempature sensor, thermostat, flushed the radiator, changed the wiring harness going to the thermostat, and the computer, and I'm still having the same code up. Is there anyone else who has been having this problem on a 5.4 motor and have fixed it. The dealership had it for two months and couldn't figure it out just seeing if anyone else has had any luck.. Thanks
I changed the thermostat. Not the problem. It ended up being a temp sensor. This was on. 6.8 liter
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Thanks for the response. I just talked with my step dad, and he said ford had replaced the coolant temperature sensor and we replaced the cylinder head temperature sensor, still not having any luck, he said next step he was gonna try was is to replace the wires to the cylinder head temp sensor to the computer and hope it could be a bad wire
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