thezonster

Ive got an 86.5 in good condition with no issues.

Can anyone tell me what is the normal position for the temp gage?

Mine always sits just above the second hash mark on the gage (the first mark above the bottom mark), after warming up, with very little variance. It always starts at the bottom mark when cold. Hot or cold weather, A/C or no A/C, not much difference. Makes me wonder if the sending unit or gage might not be right.

Maybe there is no problem at all.

jeff spahn

There isn't one. You need to check temps with an IR gun on the hoses. This will give you a reference point on your particular gauge.

davek9

Well that sounds about what I always see on both of mine and other pre S4's, best to check with IR gun as Jeff says, then you know.

Dave K

thezonster

Ive used the gun many times and it has always been fine. The main question I had was where is the normal position for the temp gage needle.

James Bailey

Normal is where ever yours happens to read all the time......

Avar928

Mine hovers just above that second line and only migrates up to horizontal if I'm gunning her hard for an extended run (i.e. kickdown and high rate of acceleration back to back or downright speeding). The needle will move back down when the rpms drop. Sometimes it'll "flick" which is probably the electrical gremlins somewhere but always check for leaks it if does happen (I had two at the hoses where the clamps weren't all the way tight causing fluid to creep out).

IR gun shows fairly consistent temps around 180F where it should be and a 30F drop between upper and lower rad hoses which one should see.

GlenL

It's not a precision gauge or sender. If the car is running well now then make that "normal" and look for changes,

Jetdriver69

My 82 did the did the same thing, a little below the second white line when warm. But the IR temps were perfect.

I replaced the engine driven fan and aux electric fan with an aftermarket single electric that is very powerful because the car would get warm in stop n go traffic. But in normal driving, the gauge reads about the same.

However, if you take out the temp gauge sensor and clean the build up of calcium (if there is any from using non distilled water in the rad) from the sensor probe and replace the wire connectors on the probe, the gauge seems to be a little more accurate. Water wetter may help lower the coolant temps if it is actually warmer than normal.

I ended up rebuilding the engine, so all cooling components were either new or very clean and the temp gauge is still running about in the same position as before the rebuild.

I carry a cheap IR gun in the glove compartment just to check if I ever have a question of the actual temps and it has never been an issue.

I guess you could replace the gauge probe, all old wiring and connections and mount an accurate aftermarket coolant temp gauge up front to get more precise readings. Apart from that, I'm living with a slightly off gauge.

thezonster

Thanks for the help