Had a new code come up on my truck. Took it to my technition.
He says the P1299 code is a cylinder head over heating. Could be caused by low coolant. ( the coolant is fine) or a faulty sensor.
He suggest I replace the sensor. He said he can't get the sensor that Ford would have it. Should I take it to Ford or get the sensorand let my tech man install it? Is there more than one sensor? What am I getting myself into?

Tim

 

Tim,

If it were me, first thing I'd do is reset the ECU. Unhook the NEG battery cable. Turn on the headlights wait 10 to 15 minutes. Turn off the headlights hook up the NEG cable.

This will erase your P1299 DTC. Drive as normal and see if it comes up again. Odds are the problem was transiant or just a sensor "hiccup". If the code comes up again post it here.

Good Luck,

Bill

 

Never heard of putting your headlights on? Is the point in doing that to make sure they don't come on therefore ensuring that you haven't grounded?

I just pull of the neg cable and and let it sit for 15 min, my code disappears.

 

Drove the truck and today cranked it up and the code was gone.
Now the thing is giving me a code through the theft light.
61. what the heck is this? Now that code is gone. What is going on?

 

The reason for turning on your headlights I would guess is to drain any residual power stored by the vehicle itself. By disconnecting the negative terminal you interrupt the flow of new current to the vehicle (electricity flows negative to positive for those that dont know). The vehicle itself may have some stored up energy (although very small amount), enough to keep the codes.

 

Hello Guys/Gals..... I am new today, and was told to post my problem on this site, because it was the best for the RIGHT answers. So, here we go.......

I have a 1998 Ford Expedition with the 4.6L. For the past week or so, I have been smelling a small odor of anti-freeze while driving. NOW... yesterday, I was driving out of my driveway (after receiving 19 3/4 inches of SNOW (in less than 24 hours) and I noticed my truck's "temp" gauge was all the way down in the COLD. I ignored it, and continued to drive into town, and all of the sudden, I had NO HEAT, and the "temp" gauge was pegged at HOT, and the OIL gauge was also pegged up as far as it could go. The "check engine" light came on, as well as the light in the upper left corner (temp protection) I think.... I got out and opened the hood, no signs of anti-freeze leaking, but I did unscrew the cap to let out pressure. I got back into the truck, and the gauge didn't change right away, but as I drove away, the temp and oil gauges went to normal, the truck all of the sudden had good heat. (no heat prior to this) BUT.... this time the truck filled up with smoke (vapors) and the smell of anti-freeze was horrible.

Now, I've been told by a couple people that "it's your heater core", and others have told me "it's your thermostat".....

The code P1299 did come up, and has came on the past few days when this happens, but this time, like I said, filled up with vapor's (BAD)

I can clear the code, and it does it all over again.

I honestly DON'T want to go through all the work to replace the heater core, if that's not what the problem is.

HELP....HELP....HELP

Thank You

 

modman - Not sure if you resolved this already. My guess is the heater core. Not sure on an expedition but on ford pickups the heater core is behind the glove box. Perhaps you should remove the cover and inspect it for leaks. You might even beable to see coolant leaking out of the seam in the heater core hosing.

Have you checked your coolant level? Not sure why a leaky heater core would give a P1299 code unless it has already resulted in a significant loss of coolant. Check coolant level if you ave not.

If you have never replace the thermostat it might be time and is easy to do. Two bolt to remove. Pull out the old O-ring and thermostat. Put in the new thermostat and O-ring. Replacement should be $6-14.

Oh, it would have been a good idea to start a new thread this one has been dormant for 9 years.

 

I have no idea how to start a new thread. I was wondering why nobody was replying.

Update: Thermostat, new coolant, and because I was in there.... New water pump. The heater core on these Expeditions are just like the F-150's, and you have to remove the entire dashboard to gain access. It's about a 7 hour job, but if you are a good mechanic, you can usually get it done within 4-5 hours.

If you ever have to do one, CHANGE THE BLEND DOOR at the same time, as the only GOOD way to do that job, is to remove the entire dashboard also.

Anyway, Thanks for the reply.

 

Glad my F150 is an '88 and my '99 is a super duty. On both, you can access the heater core simply by removing the glove box.

 

On the main Modular V8 (4.6L, 5.4L) forum page above the listings of the threads there should be a but for new threads. However this would have been better in the Expedition and Navigator forum.