Ok, I'm still convinced that my OEM temp gauge is inaccurate and I want to hook up a new Autometer temp gauge to run it in tandem with the stock gauge.

Here's my question...
The original location of the temp sender is in the driver's side head. I want to leave that in place so the OEM one will work and I can compare it to the new gauge readings.

I really can't get at the plug in the passenger side head to stick the new gauge sender in there without major pain...soooo..

I am left with the intake manifold port on the passenger front side just in front of the thermostat. Looks like a good place....but... how much will the temperature differ from trying to measure it in the head verses the intake manifold? How far off would the two readings be due to the two different locations? I am thinking that the head location will be a bit hotter due to the the combustion chambers being right there, but that eventually the intake manifold will come somewhat close to it as the engine temp stabilizes. Is this too much of an apples and oranges comparison? Should I just pull the stocker and install the Autometer gauge and be done with it? I'd really like to know if the stocker is just inaccurate and keep it there (knowing that it will be off, just verifying it right now) and leave it there until I can do a completly new dash panel with all new gauges. Any thoughts? Thanks for any replies.
Brad

 

Well, I decided to do some testing. I bought a new AutoMeter temp gauge and installed it in the intake manifold, near the thermostat housing. I think my suspicions were verified. The OEM gauge went to just above 220 and dropped below it for awhile and stabilized at about 220 degrees.

I had a little problem during the first part of the test with the Autometer gauge... they didn't tighten one of the connections on the back of the gauge and it wouldn't work... took a few minutes to find that problem.
But... after getting it up and working, the final temp the engine stablized at was not 220, but about 195-200 tops. That sounds normal for an engine fully warmed up and idling in the driveway. I think my suspicion about an inaccurate gauge has been confirmed, mine appears to be reading substantially higher than the new aftermarket gauge. I will therefore continue to run the stocker, but not worry if it gets to the 220 reading again as it seems that is normal temp for this particular gauge. At least I can get it back on the road!
Brad

 

my factory temp gauge is almost 100 degrees off.I replaced it today with another factory gauge the exact identical one and this one is only 40 degrees off.I have a scan tool so I know exactly what the coolant temperature really is.The factory gauges are horrible.Barely better than an idiot light.

 

Thank you for the reply. Wow! I never suspected it could be that bad! Glad to know that I'm not the only one with stock gauges that are off. I may just replace the whole thing with a custom panel and aftermarket gauges after this revelation! Thanks again!
Brad