Dakota Digital Erratic Temp Gauge
 

I have the VHX system in my 68 - sensor mounted in pass side head rear port. Put about 200 miles on the truck so far. The gauge seems to act normal now and again. More often than not, it will be right in the 180 range and then peg to the right and back to 180 repeatedly. Wiring is all good. Wondering if this leans towards a bar sensor, not an ideal setup with the adaptor for the 12MM adaptor fitting, or residual air in the system. Nothing leads me to believe anything is getting hot. Fans work fine and respond and desired temp, check radiator temp, not puking any fluid into overflow.

Anyone else have issues with DD temp sensor behavior?

Re: Dakota Digital Erratic Temp Gauge
 

Sounds like there is still some air in the system. Do you have a way of reading what temps the PCM is seeing when this is happening?

Re: Dakota Digital Erratic Temp Gauge
 

Check your grounds.

Re: Dakota Digital Erratic Temp Gauge
 

I agree with checking the grounds.

I run a DD sensor in the same location, I wish they just used the factory size sensor threads as that adapter they give you pushes the sensor out of the head a ways and is very thin and easy to break with a little toque on it.

That said, mine works fine, put a little heat insulation on the wire since it is close to the exhaust.

Re: Dakota Digital Erratic Temp Gauge
 

I also am running the VHX with the same setup as you. Never had an issue with it. Like others have said, make sure the motor is grounded good, and make sure the sensor wire isn't laid up on the header.

Also if you can, check your gauge temp reading with your ECT sensor (driver's side front of the head)

Bubba