Ok, my 85 GSL's temp gauge doesnt work...I dont think. When its cold (after sitting over night), the gauge reads at the first line when the key is turned on, which is normal. After its been running 5-10 mins, the choke turns off, and the gauge sits at the second line...And never moves. On the last REALLY hot day we had here in WA (90 something degrees), it will move maybe a needles width away from that second line, but never more. Whats up with this? Obviously the gauge works cause it moves, and obvioulsy the sender works, casue it makes the gauge move...Or maybe the gauge is jammed, or the sender it just bad and it sends a false signal...I dunno, it just bugs me, Id like to know how hot the car really is .

~T.J.

 

ok the needle should go to the first line when normal,
second line when hot,
3rd line means shut the damn car off,

this is from my experience with three 1st gens,

1984 gsl
1985 gsl
1984 gs

 

Hey thanks for the pic . I circled what lines I am talking about, they arent the ones you had marked...check out my pic...

~T.J.

 

well its not that far off from the first line i drew,

but i have never seen one sit that cold???

try to swap the sender before the gauge unless someone has hacked your gauges before

 

oh also just go through and check the connections first,

mainly by the rad,
i have seen many wires get coroded in this area

 

Where is the temp sensor at? Isint it the one under the oil filter?

~T.J.

 

Yeah, it's a little brass thing threaded into the engine. On the 12A, it's got one connector and one wire going to it. It's NOT the big circular thing - that's for the oil pressure gauge, which is also down around the oil cooler.

 

I had the same problem on my 85 GSL giving 'low' readings. I disconnected the connector from the brass nipple and gave it a good cleaning (directly under the oil cooler) and cleared it up.

You may want to check your thermostat, although I doubt that may be your problem since you mentioned that your choke is working correctly.

BTW, my need is at about 1/3 up the range of the gauge at normal operating temps.

 

To check the temp gauge with the key on disconnect the temp sending unit and ground it. The gauge should max out if its right. You can also check the water temp with a seperate gauge just stick it in the radiator when warmed up and see what it says.

 

So if the gauge is maxed out when grounded, then the sender is bad?

~T.J.

 

that lets you know the gauge is good. As far as the sender being bad you have to check the coolant temp against the gauge to see if they agree. Find something that you can stick in the water to see the temp. If not replace the sender since you already eliminated the gauge