My 99 f150 will read that its hot while idling for a long period but the vehicle performs fine. i just let it run for a few hours and i dont know when it started to read hot but now my check engine light is on. could that just be a result of the engine over heating, and if the engine really did over heat what sort of damage was done to the vehicle while it was just idling hot?

On some vehicles, the computer has to "learn" how to run efficiently after the battery has been disconnected for a period of time. I had an 04 Cadillac that would not idle either after the battery was disconnected for several hours. I tried everything to get it to idle right, resetting the computer, etc. Once I actually drove it around the block it started running correctly after about 1/8 mile. I could not get it to "learn" until I actually drove it, letting it run in park for almost two hours was not enough, it had to go through the process of actually driving to get everything back to normal.

the thermo fan's won't start or the gauge won't read at all depending on what you mean by therm sensor. They should feel hot and tight. Running temp is 80-90 deg C on standard street vehicles and cooling system pressure should be around 15 psi

Runs Fine but the power is down

IT DOESN'T RUN FINE THEN !!!


PO121---ETC Throttle Position (TP1) sensor Circuit Range Performance


PO505---Idle Air Control System Malfunction


PO2106---Throttle Actuator Control System-Forced Engine Limited
Power


Just take it back to whom ever did the work,they are totally
incompetent or don't know Fords

These are not easy to diagnose but I do all the time in my
driveway,with all the factory manuals & professional tools
& test equip,but no reason this comes up on fords & lincolns
& a dealer in most cases can't resolve

Take too long to explain & you wouldn't grasp it anyway

Just dont replace parts

Any suggestion of parts come back with details

This sounds like a failing ignition module. Most Auto Zone stores can test modules for free , but it has to be remoived from the vehicle.

I would check the idle air control valve, also you might have a bad coolant tempuature sensor, I would also check the air filter and repalce the fuel filter, if it hasn't been changed.

Having the proper thermostat in fuel injected vehicles is very important.They have a engine coolant sensor to tell the computer the temp of the coolant. If the engine is running too cold,(or cold all the time), the computer is going to tell the idle motor to raise the idle and to give it more fuel, which can damage the cat converter. These vehicles need a 192-195 degree thermostat. Also check the TP sensor (throttle position sensor for proper voltage) the green wire should read .7 to 1.00 volts.

There could be several concerns.
The fuel pump is weak and cutting out.
The ignition coils are getting hot and cutting off. The torque convetor in the transmission could be staying in lock up mode, This will cause the vehicle to die out , there is to much torque on the engine when at idle, causing the engine to die out.
The exhaust system could be clogged.
I would try and get the vehicle to a mechanic or dealer to check out .

it could be the a/c clutch is starting to go. They usually run ok for about an hour and then cut off. Sometimes you can shim the clutch so it is tighter, or just replaqce the clutch. Sometimes you have to remove the compressor to replace the clutch.

This is a symptom of a bad coil. The car will generally idle well, and performance will deteriorate when the car (and the coil pack)warms up.

fuses, computer?