temp gauge drops when driving...

[jrs1]

Hello I have a 1990list s13 that I just bought. I drove it for two weeks and spun a bearing. Previous owner didn't finish tell me ups about the engine problems, oh well. So i put another ka24e motor in and now my temp gauge gauge drops ain't working right. At an idle it warms. Up but once I start driving it drops below cold. It. Has all new fluids and coolent, but the top. Rad. Hose seems like it has no pressure in it. Anyone have any let's ideas??

[Mishkin_707]

Well two things, it could just be air in the cooling system or your thermostat, when my thermostat went bad on my single cam it did that to me, it would warm and when I drove the car it would cool all the way down

[jrs1]

Well I ended up talking the water outlet off and found my problem. There was no t-stat to begin with. So I put two and a new one in with a new gasket and it works great now.

[Mishkin_707]

LOL, nice, glad you found out the problem, just make sure the is nothing else wrong with the motor cause some jerks pull out the thermostat when the motor is overheating and are too lazy to research why it's overheating

[jrs1]

Well I got the motor from the junk yard and put it in. Since I put the t-stat in the cars been running great!!! Until yesterday. My buddy was driving behind me and said when I got on it that white smoke when was coming out the exhaust. Firstt thing to my mind was the head gasket. But the oils not milky and the coolents not muddy, its a light brown but not bad. So would it be the head gasket?? Im still new too the 240 game... :-/

[Mishkin_707]

How bad was the white smoke? What was the temp outside that day? If it was white with a blueish tint that means there may be coolant in the mix, also how does your exhaust smell? Rich, lean, sweet or normal?

[jrs1]

The exhaust smells normal. Granted I see a little carbon on the bumper. And I didn't see the smoke drone inside my car. And it was at night