I installed the coolant temperature sending unit on my 1998 Ford F-150 and also bought the coolant temperature sensor. I can't find where to install the temperature sensor. Where does it go or is this the sending unit and sensor all in one? My truck has been bringing up codes 171 and 174 leading me to believe the problem might be with those items. What are your thoughts? The parts store employees are giving me different stories on being 2 separate things or all in one.
They are two separate units located on the top end of the motor, and can be located off the intake manifold plume. They are neighboring independent sensors.
〉 Answered on Apr 8th, 2014 by Amanda J. Pierce, MBA "AJ", Certified Mechanic, Project Coordinator; Primavera Scheduler at VIGOR Alaska Industrial Shipyard & BizzM3ch Solutions
The coolant temp sensor is usually near the thermostat housing. I would need to know what motor is in the truck to give an exact location.
P0171 and P0174 are codes indicating that the engine is running lean (The computer is adding fuel to make up for increased oxygen content in the exhaust stream). Unless the coolant temp sensor is telling the vehicle it is cold even after the engine warms up, this is not going to cause your issue. There are many things that can cause a vehicle to set these codes - MAF sensor, vacuum leak, exhaust leak, clogged injector, worn out spark plugs, etc. This is one better left to a professional technician as the code by itself will not give you the answer you are looking for.
〉 Answered on Apr 8th, 2014 by Helaine Kurot, Owner/Technician at 360 Automotive