Hi again. My temp gauge is acting up or is it? Its going up & down, I've already filled it with coolant the other day. should I just install a new water pump & thermostat?

KC

Coolant gauge should be at cold when you first start the engine, and then
move to somewhere around halfway (and stay there) when the engine is
fully warmed up.

If the gauge moves towards HOT while you are stuck in traffic, or drops
towards cold when cruising at night (or when it is cool out), the thermostat
is probably stuck open.

Changing the water pump should not be necessary, but putting in a new
thermostat would be a good idea if it acts as above.

Cheers... jondee86

The waterpump has much less then a 1 in a million chance of affecting water temp. NEVER even think about it unless its leaking, causing overheating from loss of coolant, or seized/doesn't turn freely/shaft really wobbles from really worn bearings.
The thermo. either works or don't, it cannot not move as fast as your gauge is moving.
Clean the wire connectors to the sending unit.

Thank you gentlemen, I will change the thermo & clean the wires tomorrow. Have a good evening or good morning.

KC

Hi guys! I did changed the thermo already and still acting up, any idea?

KC

Cheers... jondee86

I ran into this problem too, and it ended up being my temp sender switch. I got a cheap one at autozone and my temp gauge needle was all over the place. Got an oem temp sender switch afterwards and no more problems.
You really do get what you pay for. Lol