it should not go up and down.

check the coolant level. check the thermostat.

Roy

Answered by ASEMaster6371 (expert)
24,836 answers provided

Well i did change coolant and look at thermostat. Thinking maybe faulty thermostat, i tested it in a pot of water, slowly bring the water to almost boiling and it was very slow to open but closed a little quicker when put in cooler water. Does this indicated a sticky or faulty thermostat? Didnt look like a standard thermostat either. Are they sold separately or do they come complete with the housing?

Response from neilconnah
1 question asked

as the stat opens and closes.the heated water gos into the rad.and the cool water goes back in the engine.make sure the rad. fan is working.the temp.gauge will move up and down slightly when the stat opens and closing.remove the coolant and fill with water. then remove the upper hose at the radiator.start it and u should watch the stat when it opens all the water will pour out the upper hose.when the stat opens

Answered by cadieman (expert)
2,857 answers provided