Have a 1991 Dodge Daytona. Temperature gauge is all over the place--hot one second, and normal the next.
Important facts:
Car sat for two years. The "head" was replaced with a new one.
Oxygen sensor was recently replaced.
Has 210,000 miles.
Idles smoothly and accelerates fine.
Not sure if it could be a faulty mass air flow sensor, a thermostat, or something else.
What could cause this rapid temperature fluctuation?
2007-11-23 11:16:37 · 5 answers · asked by carputer1 1 in Cars & Transportation ➔ Car Makes ➔ Dodge
The first thing to do is change the thermostat and see what happens. If it was a stopped up radiator, it would go to hot and stay there. Same with bad head gasket or water pump. And it doesn't have an air bleed in the system or mass air flow sensor.
2007-11-24 04:56:20 · answer #1 · answered by Jackolantern 7 · 0⤊ 0⤋
First thing to check is for air in the system. There is a bleed off valve in/on the head at the highest point of the water system. Warm the engine up and open this stopcock (usually a 10mm wrench) and release any air in the cooling system. You will know when all the air is out because a steady stream of water will come out of this stopcock. If this does not cure the problem, you may have a faulty thermostat. Change the thermostat, bleed the air and recheck the temp. If still a problem, then you have a faulty head gasket, but since you put a "new" one on and you are sure its surface was flat, then you may have a cracked water jacket in the engine block. Let's hope for air in the system.
2007-11-23 11:30:49 · answer #2 · answered by rex_rrracefab 6 · 0⤊ 0⤋
when the thermostat sticks on them they will do this ,then when it opens is when you see the drop in temperature,if your sure its actually running hotter have a shop check it,and they may want to flush everything out real good on it,to make sure the coolant is circulating good in it,other than that you could have a faulty temperature sending unit that is sending false signals to the hand,a bad water pump can also do this,if the fins on it get worn down some they wont circulate the coolant fast enough,have it diagnosed ,so you don't mess it up driving it,if it does get hot,it will do harm to it,good luck on it.
2007-11-23 12:28:56 · answer #3 · answered by dodge man 7 · 0⤊ 0⤋
If it is not over heating and there is no coolant loss, it is nothing to worry about.
What could be happening is that the thermostat is opening and closing as the radiator does its job.
While a higher pressure radiator cap may help the temperature to stabilize I am not sure it would be worth the cost. If you can not get enough heat to meet your needs try a higher pressure cap.
2007-11-23 11:44:19 · answer #4 · answered by teamepler@verizon.net 5 · 0⤊ 0⤋
go to a mechanic
2007-11-23 11:24:40 · answer #5 · answered by Anonymous · 0⤊ 0⤋