SeaPro
Active LVC Member
Story:
The car was working fine until it sat for about a week. I Went to drive it and 5 minutes later it threw codes P1285 (Cylinder Head Overtemperature Condition and P1299 (Cylinder Head Overtemperature Protection Active). The engine temp shot up and the car went into protection mode. I got home, parked the car and went to bed. The next morning It drove perfectly, as if nothing happened. I drove for two weeks (about 500km) with no issues.
The car sat for another week and all of a sudden I encountered the same problem - 5 minutes down the road it overheated. This time it didn't go away. It overheated almost instantly. I thought it was a faulty thermostat so I opened up the housing and removed it (hoping it would at least be drive able). This didn't solve the problem however while I had it apart I noticed the inside of the housing was severely deteriorated and the original thermostat was not sitting properly. Plastic bits had actually broken off all over the place. Now I began to think the radiator was clogged up with plastic because of how quickly it would overheat at idle.
Solution:
I ordered a complete thermostat and housing from rockauto for $90 CND (Ford wanted $350 for these parts). I drained the entire system of coolant then removed the old housing and reverse flushed the radiator with a hose. I didn't remove the radiator, just attached the hose to the upper radiator hose using duct tape and ran lots of water through it. Then I connected to the bottom hose and did the same thing. The radiator flushed perfectly so I was confident there was no blockage, however I used a strainer to filter the water coming out and noticed a few very small plastic pieces (nothing too large though). I installed the new thermostat and housing. While I was at it I changed the water pump because it's very accessible with the thermostat taken off and hoses out of the way. I was worried one of the plastic blades of the impeller may have broken off and clogged the radiator (yes I realize this is very unlikely).
Once the water pump and housing were back in place, I reassembled the air intake and ran water through the thermostat housing (with the radiator still disconnected). I started the engine with the heat on and flushed the rest of the system.
Once that was all done, I blew out as much of the fresh water from the system that I could and put everything back together. When I tried to fill the system back up with Prestone green premix coolant (adding a bit of concentrate for any residual fresh water) I could only pour about 4 liters in. I Started the car and poof, it overheated instantly. The heating system also stopped working at this point. It was cold and dark out so I decided to give up for the night.
The more I thought about it that night, I realized there was likely air in the system and that I had probably bled it wrong. The next day I went back and bled the system properly following the exact proceedure found in the manual and here and everything was fixed. No more overheating. I've driven for a week with no issues. So far so good!
Conclusion:
I know most of you insist on changing all plastic parts (and I'm sure this will come back to bite me in the ass eventually) but upon inspection of all hoses and plastic components, they seemed fine. It was only the plastic thermostat housing that showed any real wear. The base of the thermostat was the largest piece of plastic broken off / missing.
I'm not totally sure what caused the overheating to occur in the first place. I feel like the faulty thermostat could have caused the problem, but am not totally convinced. The original water pump was fine upon removal, but it was only a matter of time before it went. I didn't find any large chunks of plastic in the system however they may have slipped past me. I find it unlikely there could have been air in the system before all of this happened. The real test will be that of time, but for now the car is running perfectly (famous last words). Hope this helps somebody!
Home flushing system. I was quoted around $250 to get a system flush, this took 5 minutes.
The car was working fine until it sat for about a week. I Went to drive it and 5 minutes later it threw codes P1285 (Cylinder Head Overtemperature Condition and P1299 (Cylinder Head Overtemperature Protection Active). The engine temp shot up and the car went into protection mode. I got home, parked the car and went to bed. The next morning It drove perfectly, as if nothing happened. I drove for two weeks (about 500km) with no issues.
The car sat for another week and all of a sudden I encountered the same problem - 5 minutes down the road it overheated. This time it didn't go away. It overheated almost instantly. I thought it was a faulty thermostat so I opened up the housing and removed it (hoping it would at least be drive able). This didn't solve the problem however while I had it apart I noticed the inside of the housing was severely deteriorated and the original thermostat was not sitting properly. Plastic bits had actually broken off all over the place. Now I began to think the radiator was clogged up with plastic because of how quickly it would overheat at idle.
Solution:
I ordered a complete thermostat and housing from rockauto for $90 CND (Ford wanted $350 for these parts). I drained the entire system of coolant then removed the old housing and reverse flushed the radiator with a hose. I didn't remove the radiator, just attached the hose to the upper radiator hose using duct tape and ran lots of water through it. Then I connected to the bottom hose and did the same thing. The radiator flushed perfectly so I was confident there was no blockage, however I used a strainer to filter the water coming out and noticed a few very small plastic pieces (nothing too large though). I installed the new thermostat and housing. While I was at it I changed the water pump because it's very accessible with the thermostat taken off and hoses out of the way. I was worried one of the plastic blades of the impeller may have broken off and clogged the radiator (yes I realize this is very unlikely).
Once the water pump and housing were back in place, I reassembled the air intake and ran water through the thermostat housing (with the radiator still disconnected). I started the engine with the heat on and flushed the rest of the system.
Once that was all done, I blew out as much of the fresh water from the system that I could and put everything back together. When I tried to fill the system back up with Prestone green premix coolant (adding a bit of concentrate for any residual fresh water) I could only pour about 4 liters in. I Started the car and poof, it overheated instantly. The heating system also stopped working at this point. It was cold and dark out so I decided to give up for the night.
The more I thought about it that night, I realized there was likely air in the system and that I had probably bled it wrong. The next day I went back and bled the system properly following the exact proceedure found in the manual and here and everything was fixed. No more overheating. I've driven for a week with no issues. So far so good!
Conclusion:
I know most of you insist on changing all plastic parts (and I'm sure this will come back to bite me in the ass eventually) but upon inspection of all hoses and plastic components, they seemed fine. It was only the plastic thermostat housing that showed any real wear. The base of the thermostat was the largest piece of plastic broken off / missing.
I'm not totally sure what caused the overheating to occur in the first place. I feel like the faulty thermostat could have caused the problem, but am not totally convinced. The original water pump was fine upon removal, but it was only a matter of time before it went. I didn't find any large chunks of plastic in the system however they may have slipped past me. I find it unlikely there could have been air in the system before all of this happened. The real test will be that of time, but for now the car is running perfectly (famous last words). Hope this helps somebody!
Home flushing system. I was quoted around $250 to get a system flush, this took 5 minutes.