'86 N/A Z31 Having Temp Issues: Please Help

[Bates]

The car just got a tune up, and is running fine (despite a sticky lifter), brand new thermostat as well. The car starts and idles just fine, never gets hot, which is the problem, it is too cold. The upper radiator hose never goes past 130 degrees, and the bottom is colder still, maybe 60. The operating temp for the car is 180 but it never gets that high. The temp gauge in the car is not working (I think the wiring is bad or the gauge is bad, because when crossing the wires for the sender, the needle did not jump).

My questions are:

1- Could the thermostat not be opening up all the way?
2- Could my radiator be clogged?
3- Is it common for the temp gauge to just go bad?

My mechanic is going to try a second brand new thermostat just to be on the safe side, and then we are going to try an after market temp gauge, but I just want some more input just in case the problem still persists. Could it also have something to do with the cylinder head temp sensor (the one by the thermostat housing.)

[jpalamar]

Your mechanic should have a scan tool that can tell what the actual engine temp is(I know nothing about computers in older cars, but my OBD2 is like that).

It is really easy to tell when the t-stat opens(an amature mechanic should know) because you will see the fluid in the overflow circulate. its cold outside so it will take a long time to hit operating temps just idleing, especially if the hood is open.

First thing I would check would be the t-stat. Is the gasket good? Is the t-stat seated correctly, Is it closed all the way? Does it open(you can put it in boiling water and if it opens it should be good, put it in ice water and it should close all the way. I'm seen a few t-stats out of the box that were bad.

Check your oil, see if there is any coolent mixed in(it would look like chocolate milk typicalyl if it is).

[Bates]

The thermostat is opening, we just can't see if it is opening all the way because it is buried, plus it is a major pain in the ass to take out. The car is does not idle at standard operating temp, we checked it (We let the car idle for about 15-20 mins and just monitored it). The oil is fine, just put in fresh oil, no coolant is mixed in with it.

[jpalamar]

If the car isn't getting hot, then most likey the t-stat isn't closing all the way or isn't seated right.

[Bates]

Originally Posted by jpalamar

If the car isn't getting hot, then most likey the t-stat isn't closing all the way or isn't seated right.

That was my initial thought too, but the temp gauge isn't moving at all. Shouldn't I see some type of movement in the needle?

[jpalamar]

Did the guage work before you did the t-stat replacement?

[Bates]

Originally Posted by jpalamar

Did the guage work before you did the t-stat replacement?

Dont know lol. This is the first time I have seen the car running since I bought it like 2 weeks ago.

I bought the car non-running because it blew a timing belt, which I thought the engine would have needed to be rebuilt, but I lucked out hard and no valves were bent and the engine was fine.

[Bates]

Yea, so we found the problem. The water temp gauge (which on my car is on the lower intake manifold under a **** ton of wires on the passenger side) wasn't connected all the way. We were dumb but we could barely see the damn thing lol.