Have any of you done this? That is withough dismantling the upper intake? Seems to me it might be hard/impossible to get out of there withought the intake removed.

If you have what tools, techniques have you used.

 

I'm not sure you can get up in there without removing the intake. You can try removing the alternator first.

That sensor is in a dry hole and the brass bulb stays clean. What can happen, the wire breaks inside the insulation at the connector. So, - The CHT harness is a separate little harness that totally disconnects from the main harness. If you have small hands, you may be able to disconnect it, pull it from the vehicle and continuity check the wires. I've had to make a new one.

 

Yea, here's the CHT harness I repaired. Well, -I just made a new one. The old - wire was losing contact intermittently inside the insulation. They get old. -

 

Ya thats what mine is doing, It will go away, (gauge goes to cold) and the engine will start knocking hard when im towing. Then all the sudden the temp will go back to the middle of the gauge and everything runs smoot.

I think i got a P0118 or something and also another code for the CHT sensor and knowing there the same assumed the sensor was bad. Where in the harness does it tie back into?

 

The code you posted is for the ECT or CHT, but only ECT in this description....

http://www.obd-codes.com/p0118

 

thats because its the same sensor on the later years of 97-03 style. 97-98 used a ECT sensor in the coolent, that ran the gauge. And it ran a CHT in the head to run the computer.

Now both the gauge and Computer run from the CHT.

 

No, that's only for the 5.4L. You didn't specify the engine, so you'll get mixed posts.

 

ehh no its for the 5.4l and the 4.6l. I know because my truck was a 99 4.6l and now has a 02 5.4l. I didnt change one thing on the computer harness. Every thing hooked back up to the exact same sensor.

Buy your right i forgot to fill in my specs.

 

Here we go

 

https://www.f150online.com/forums/ge...re-2-them.html

 

I know some , if not all 2000 4.6L's had both ECT/CHT sensors. The 5.4L had the ECT/CHT in 98. 99's CHT only.

So - the 99 4.6L's indeed had a ECT and CHT sensor. Where's you old engine? Take a look.

 

Its in my barn. Question is where did the plug goe that goes to the engine temp sensor. And how come my gauge still works with out the ECT sensor on my 5.4l? The computer is still a 4.6l computer. And its reading my CHT sensor for both the gauge and ECM tuning.

 

I just did it. I removed the alternator along with the support bracket. Pull the insulator forward and sever it where it connects on the side. Pull the side piece to you and pop the two plastic fasteners out and pull that piece out. You can see the CHT and get a long open end 3/4 wrench and loosen. I had already pulled the fuel rail on that side to disconnect the jumper harness in the back. I only pulled the rail up out of the way. Unscrew Cht and take it out. The local Ford dealer didn't have just the jumper but they are available on the net for under $20. the jumper harness has
d been routed wrong by a shop that did some work on it. It had too much tension on it and was frayed in three places by movement of an actuator back of engine. New CHT and harness for under $50. there is always more than one way to skin a cat. I was amazed at the amount of wrong information out on the net and in a manual I bought for this vehicle. Had to ferret out things myself. This was done on a 2005 Expedition XLT 5.4L

 

I have a 1997 F150 4.2 v6. I believe I have located the spot where the CHT sensor SHOULD be but IS NOT. There is just a threaded hole on the back side of the head up near the firewall. I cannot see any plug or wires that would have connected to the CHT sensor either, and I have even gone so far as to use an inspection camera.... still nothing. My question is can anybody tell me where the other end of the CHT sensor wires begin from so that I can try to follow them to see where the wires broke off? Then at least I could attempt to replace the plug and sensor. If anybody can help me with this it would be much appreciated.

Thanks

 

The 97 4.2 does not have a CHT sensor, it only has the ECT sensor.

You're looking for something that isn't supposed to be there.