prize for the right answer TEMPERTURE FLUCTUATIONS 0N 95 CIVIC-

I have a 1995 Civic. I've noticed that recently, the temperture gauge goes
from just under half way to sometimes 3/4 while I am driving. It goes up
for a few minutes then goes back down again. This cycle continues
throughout the driving and usually starts about 20 minutes into the drive.

I had the cooling system pressure tested and the radiator's flow checked
and all seems to be fine.

What could this be? Could the thermostat be going?

Thank you all in advance!

 

Since there is apparently no head gasket or coolant level issues, the
thermostat is sticking in the open position.

Stewart DIBBS

 

Change the thermostat. It is not operating properly.

 

Your cooling fans are not working as should be. The two fans come on
independent of each other. The same thing happened to me a while back.
There is a heat sensor/relay that needs to be replaced.
Question-Does both fans come on when you turn on the AC??
Start with cool car
Open hood
start motor
observe fans
turn on AC
both fans should be on
***
In normal operations when temp reaches a set temp one fan comes on, if temp
keeps going up (hot summer day/stuck in traffic) in other words, no unaided
air flow, when temp reaches higher preset temp the other fan comes on.
It sounds to me as your lower temp sensor fan is not coming on. When the
higher temp is reached the fan comes on, cools things down and turns off.
Temp rises to lower setpoint fan 1 should come on but does not, temp rises
more, fan 2 comes on. Then the cycle repeats.
Happy cruising