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Checked codes after my 99 Dodge Dakota Sport started stalling after warming up. I can start it cold, but soon it acts like it is going to stall and then stops. Difficult to restart until engine cools again.

Im getting 3 codes, 123- Throttle Position Sensor, 320 Crank Sensor, and Cam sensor. All show no communication.

Any suggestions would be a big help. thanks
 

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Welcome to the Z Family from Southern Georgia!
Glad you decided to join us.

This post discusses cam and crank sensors. This post also discusses sensors. Maybe they will offer some insight.
 

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Checked codes after my 99 Dodge Dakota Sport started stalling after warming up. I can start it cold, but soon it acts like it is going to stall and then stops. Difficult to restart until engine cools again.

Im getting 3 codes, 123- Throttle Position Sensor, 320 Crank Sensor, and Cam sensor. All show no communication.

Any suggestions would be a big help. thanks
P0123 is TPS voltage high. TPS sensor input (to PCM) is above the
acceptable limit..usally 4.5 volts. These are easy enough to check
BEFORE replacing..with a voltmeter, one lead to engine ground and the
other probing through the insulation of the center wire on the plug..
1) remove throttle body air breather so that you can see the throttle plates
2) turn on ignition key BUT do not start engine.

PO320 No crank(sensor) reference signal at PCM detected during engine
cranking. This is a hall effect sensor..known to have weird failure
symptoms. There is no effective way of testing these are they are
short duration pulses. The crank sensor is used by the PCM to facilitate
injector timing in relation to each cylinder on the compression cycle.
3) Measure CLOSED TROTTLE (should be around 0.5v)
4. Move throttle plate by hand from closed to fully open.
Voltage should increase smoothly to a maximum of 4.5 volts (or maybe
slightly under)
This is a 5v range sensor.
if you get that reading, the TPS may not be the cause of the symptom
your are indicating.

No communication..don't know what that means. These are individual
sensor inputs to the PCM, they have nothing to do with the CCD
communication bus between microprocessor controllers on your vehicle.

BTW..the cam sensor is the same kind of hall effect type and has been
known to cause these kind of symptoms. In my case it was a 99 Dodge
Ram that would start provided it was cool..run for a few minutes then
shut down..and not restart until the engine cooled down sufficiently.

No check engine codes provided in my case. Had to have the truck
towed to a local garage because it was so unreliable.

Here's what they did to fix it.
1. Changed out crank sensor..same problem,
2. Changed out cam sensor..problem went away and truck ran reliably,
 
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