I have an 84' Z28 w/85 mph cluster. Swapped it out for the 145 mph cluster. Everything seems to work, except the temp guage. It works, but it keeps telling me that I'm overheating. I WANT TO KEEP THE ORIGIONAL GUAGES!. I know about the guages being inaccurate, however, they used to work at some point, so how to check the guage?

Is there some different sending unit or some other thing I am missing to make the upgrade accurate? The car is not running hot, but it is telling me it is. Different sending unit? Faulty wiring?

BACKGROUND:
new gauge (from junkyard, I have 3)
new sending unit
new coolant temp sensor
new thermostat
new waterpump
new belts
new hoses
raditator 6 yrs old, but no leaks and has been flushed and cleaned

So it is most likely not mechanical.

 

well what year did the 145 cluster come out of? its possible the 145 cluster car calls for a different temp gauge sending unit

 

not sure. swapped them out a few years ago. how would i find this other sending unit? I would pay $10.00 to just try that out. this gauge thing if frustrating.

 

well i did a quick search and found that different year camaros use different part numbers for the temp sensor. i would go and try a sensor for a different year camaro

 

where to search? Autozone?

 

I am willing to bet it is either a different sender or something in the wiring eg. short or loose connection. How do I test the wiring to see if it is good?

 

haynes manual doesnt say anything on how to test the circuit. try unplugging the sensor and see if the needle position changes when the key is on.

 

Can you swap the original temp gauge into the 145mph cluster?

That way you wouldn't have to buy anything and it worked with what you already have.

 

I think it is the same temp gauge in several MPH variations.

 

2 OTHER IMPORTANT NOTES:

My ECM is disconnected, I believe, would that effect the temp gauge?

And what does the coolant sensor do in a belt driven fan model?

 

There are some electrical issues between clusters (which is why I always suggest simply swapping the speedo head):

https://www.thirdgen.org/forums/inte...atability.html

JamesC

 

I've used the same type of temp sending unit on countless LG4's, LO3's, LB9's and many other 'mutt' engines I've built over the years. The only difference I've ever noticed is when swapping from a dummy-light temp "switch" to a gauge "sending unit".

Jim's right, Probably a problem with the printed circuit on the replacement cluster,................ Re-install the original cluster with the 145 Speedo head !

 

I can't I did the swap years ago. How do I know if I have a gauge sender?