Dakota digital temp issues
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Joined: Jun 2009
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From: Manitowoc wi.
Dakota digital temp issues Posting this to help others who may have inaccurate temp issues with a Dakota Digital VFD or VHX gauges.My normal cruise temps would read approximately 20 degrees lower than stat temp. I have the temp sender mounted in the pass.side head at the rear. I had to use an adapter just as most have to. I ordered an aluminum extended reach unit from an online vendor to ease installation. After some reasoning, I came to the conclusion that the extended reach adapter was wicking the heat from the sender. I called Dakota Digital tech line to see if they had any solutions. It turns out that they must have rethought their initial design and extended the probe on the sender to better submerse it into the coolant stream. I've ordered the new sender and a shorter adapter which will fully submerse the unit in the cylinder head coolant flow path.So, if you run either style of these gauges. you really need to run the new # sending unit. The part # is 150021 and can only be purchased direct from Dakota Digital.
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Joined: Dec 2017
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From: Bossier City, Louisiana
I'm seeing the opposite of your situation with the Dakota Digital HDX gauges in my 70 El Camino. I'm about 20 degrees hotter at my DD temperature gauge than what the PCM is seeing. The DD gauge uses the passenger side rear hole for their sending unit and the PCM uses the drivers side front head hole for its sending unit and its a new sender for the PCM. I'm not certain which gauge is correct but in no case is the vehicle running too hot. I also needed the DD adapter and I'm wondering if I have excess heat spillage from a header pipe that raises the temp to the DD sender?
Any advice? Would it help for me to also call the DD Help Desk?
Rick
Any advice? Would it help for me to also call the DD Help Desk?
Rick
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Launching!
Joined: Jun 2009
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From: Manitowoc wi.
B52, typical head temps are usually 20 degrees hotter than the stat temps.My sender was only suspect at cruise reading 175 degrees due to the fact that the aluminum adapter was approx. 2 inches in length. This would dissipate heat too rapidly as the airflow around the adapter would increase while cruising. At idle, the temps would increase rapidly to 225 as water and airflow decreased. I would call tech support to see if the new sender would apply to your versions of gauges.
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From: Manitowoc wi.
B52 I believe gm engineers calibrated the coolant temp sensors to compensate for the higher temp readings typically seen in the heads. Coolant flow through engine also plays a part in this, as at any given point there could be as much as 15-20 degrees difference throughout the block and heads. Because the factory coolant sensor is located nearer to the thermostat,this could be one reason it may read closer to the stat operating temperature. I am not an engineer,but I can tell you that after an extended idle period that my gauge would read 225 degrees before the fans would engage. The fan engagement temp was set at 215 on and 205 off. When reading the temp sensor through a scan tool,the numbers were right on the money for fan engagement/disengagement.Additionally, the coolant temp sensor at a cruise read within 2 degrees of the stat, while my gauge sensor would read 175 degrees. I believe the main culprit in my case is the extended aluminum adapter was dissipating heat from the airflow at cruise . At idle with no airflow, I saw what I consider to be a normal cylinder head temperature of 225 degrees. What DD did was to extend the gauge temp sender probe by 7/16 inch to ensure coolant flow past the sender, in an effort to eliminate heat soak/hot spotting. I also think that heat from the headers can play a part in this, especially at extended idle conditions where airflow across the outside of the sender is non existent.You could, loosely wrap a piece of foil around the sender in an effort to reduce header heat soak as an experiment, This may confirm your suspicions. At any rate I will report back with my findings.
There actually is a significant temp difference between the front of the driver head and the rear of the passenger head. I’ve noticed it many times with many different gauges, after some reading on it seems that there truly is a difference
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From: Manitowoc wi.
As a follow up to the original post,the shorter adapter along with the newly designed sender has my temp reading within 1-2 degrees both at idle and cruise when comparing it to the factory coolant temp sensor.The probe on the new DD sender is indeed 7/16 longer than the original unit they sent me with the gauge kit. The new temp sender adapter is also 1 1/2 shorter and is made of brass instead of aluminum. This now puts the probe directly in the coolant stream. My theory on head temps seems to be unproven as the fans turn on and off at the exact temps they were programmed at /215 on and 205 off.
