I've been having problems with coolant sensors, I've replaced the coolant sensor as well as the cylinder head temp sensor. Still getting codes for the cyclinder head temp sensor low output, cylinder head temp sensor high output as well as an cylinder head temp sensor intermitent code now.

I've replaced all pig tails and traced wires and can't find anything broke anywhere.

Does anyone have any ideas on what the next step would be or maybe have had this problem.

Ever since the cylinder head temp sensor started acting up I'm getting about 9.6mpg on days when it's between 40-45 days when its 40-below I'm lucky to get 9.2mpg, also the idle is constantly kicking up to around 2000rpm and then will drop back to 800rpm.

Mornings when its in the teens it's hard to start and idles rough until it warms up, I'm told this has to do with the cylinder head temp senor not telling the PCM the correct fuel ratio and it's thinking the motor is either to cold or to hot all the time which either shuts down cylinders and turns them into "cooling mode" and when it thinks the motor is cold it just keeps dumping fuel, which in turn is the high idle issue as well?

If anyone can help me out with this it would be greatly appreciated. I had gone to the Ford dealer to get the CHT sensor replaced and they wanted to charge $600+ to do it, tried telling me the intake had to come off. All you have to do is cut a wrench bend it a little and remove the alternator and you can get right to the sensor.

 

Its not as easy as you say, but okay.
Try tackling it on your own and then get the codes wiped out.
Let us know how it goes.

 

Try posting this in the V-10 forum. (Unless you already did)

 

What is the condition of the engine ground straps?

 

I've already replace the CHT sensor and coolant sensor, and cleared all the codes. Ran like a top for a day, check engine light came back on and all codes came back. Next step is looking like wires somewhere.

 

No I didn't, this is all new to me my apoligies.

I cleaned up all the ones I could find, Haines book doesnt tell me to much as far as where they all are.