So I popped the hood the other day...Look in my coolant resivoir and its empty! First thing I think...DAMN PLASTIC INTAKE! I was relieved to find that the loss of coolent was, I hope, the thermostat housing. So I bought new gaskets and put the 180 t-stat back in(I put the 195 in it a couple months ago). Now the temp gauge constantly fluctuates between about 165 and 185...Up and down, up and down....Hmm, any Ideas?

Has your upper intake ever failed before?

mine does a lot of fluctuation with the 195 in it. I find what works is if you tap on top of where the temp gage is with your fingers, mine usually goes back to were it should be!

Does it go consistently up and down at the same time interval?

my car was doing the exact same thing. i put the 195 back in for winter. the 180 just does not get it for cold weather.

No.

Yes, from what I observed. It goes down, then about 5 seconds later it goes up, and 5 secpnds later it goes back down.

When I had that problem with my 89, it was a bad themostat. Once I replaced the thermostat, the needle stayed in the same place.

Well I figured since I'm changing the gaskets anyway, I might as well put the 180 back in.

Well I changed the thermostat and it'* still fluctuating. Basically replaced a stant 180 with another one. It floats between about 195 and the next bar to the left of 195, back and forth. Could this be a result of a leak in the system? see http://www.bonnevilleclub.com/forum/...ic.php?t=14515