The Coolant temperature sensor on my '93 Dakota measures too low when I
check the resistance according to the shop manual.
Unfortunately, I haven't been able to find a replacement for this sensor
at parts stores or the local Dodge dealer.
The sensor on my Dakota is small and has only one pin. The parts stores
have a larger unit with two pins.
Any one else have this problem?
Is the faulty sensor likely to cause any problems? The gauge when the
engine is fully warm is just above the C.
No, the pin on my sensor is a flat pin about 1/16 wide.
I guess, I am going to take the sensor out and see if there are any part
numbers or other information on it.
It looks like it may be hard to get at as it is behind the alternator
and other stuff.
Tom Lawrence wrote:
If I unplug the sensor and turn the ignition on, the gauge reads low
(all the way to the left). If I short the lead (Still unplugged)to
ground, the gauge reads high (all the way to the right). So I am
confident I am dealing with the coolant sensor. It is just behind the
The service manual suggests the correct resistance should be between 10k
and 13k at 70 degrees. The sensor reads 2k. I haven't checked the
sensor with the engine warm. I know this seems backward and the gauge
should read high, but 2k is not a normal reading, so I thought I would
change out the sensor. By the way, the temperature gauge has read low
since I bought the vehicle last year.
The only reason I am concerned is that I am still having stalling and
backfiring problems and have replaced the catalytic converter, muffler,
distributer cap and rotor, spark plugs, ignition wires, O2 sensor, fuel
filter, air filter, and EGR valve. I have also checked for vacuum leaks.
So I am trying to fix anything that is possibly related.
The backfiring occurs when I am driving at a constant highway speed and
encounter a hill. As I gently apply more throttle to maintain the
speed, the engine will briefly stall and backfire through the exhaust.
If I let off the gas for a few seconds, the engine will begin to run
smoothly and everything seems normal. On a 400 mile trip, this may
happen 2-3 times.
I believe that the coolant sensor is one of the inputs the computer uses
in setting the timing, but you are right that I am probably wasting
energy with this.
I will check the distributer bushings and the distributer position
sensor as well.
There are two distinctly different components;
1) Temperature 'sending unit' which inputs to the dash gauge.
2) Coolant temperature 'sensor' which inputs to the PCM according
to coolant temperature.
Device #1 has nothing to do with engine operation other than to
let you know if the engine is overheating, and it's not very good
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