68 Coronet. It seems that all of the guages are reading wrong. When Fuel tank is full it reads between 1/2 to 3/4 full, temp guage reads a hair over 170 but i check the temp of a radiator hose and its closer to 195, oil pressure reads a little over 20 when driving but with a manual guage installed it is around 45 at same load, Volt guage reads 3-5 volts but place a multi-meter on battery and its 14.4 v. Any ideas? I have checked the engine grounds and for any loose connections but no luck.

Thanks for the help

 

I am going to guess that the electromechanical voltage regulator for the gauges (yes the gauges have their own regulator) is starting to go bad.
If you can find the article called "Gauge Rage" from the pages of Mopar Action magazine, it tells you the "fix" for this problem. I think Allpar has this on their website. The fix involves installing electronic components to replace the troublesome factory piece.

 

Read this article first.
_how to repair and diagnose instrument gauges/instrument voltage regulator

 

I would have thought the instrument cluster voltage regulator also but two things here first the IVR does not control the amp and or volt meter so that gauge would be a seperate issue. Next, I have seen a few of these go bad and from what I have seen is that they work ok or not at all. There are a couple of dash grounds I would check first. I know of one by the driver side kick panel (there are probably more not really sure)

 

I have checked all of the grounds and they are good with .1 to .2 ohms. I am going to try this IVR if I can find one tomorrow, if that doesn't work then I guess out is going to have to come and check the board. I did do some reading up on this today and the IVR seems like a good place to start. I haven't worked on anything this old in a looooooong time.

 

Nice to keep the factory look but I hate OE gauges, it's like peeing out the window to see which way the wind is blowing

This will keep the $$$ invested in your engine safe and sound

 

Good grief!!!
Where is the clock on that dash?

 

Time is overrated anyway trust me lol, nothing like knowing all the vitals and Scamp Tramp looks like he is into knowing everything going on, nothing wrong with that just not everybodys style or needs. Must say I am impressed by his layout with good use of the space with everything in view, nice job Scamp