94' Saturn SL2 -

My girlfriend has a 94 Saturn SL2. She bought it a few months ago with
78k miles on it. Since she's had it, the engine revs up high for about
ten seconds after start. It also did the same when she puts the car in
park before turning the engine off. A couple of times, the came home
with the coolant boiling out of the tank. The last time it did that, we
took to the shop. They said that they would have to change the coolant
temperature sensor, the tranmission fluid temperature sensor, and the
air temperature sensor. Needless to say, they say that the bill will go
up to $650. My girlfriend had a friend who also had a shop. He took it
to his shop and he said all he did was take the termostat out. Not
replace it, but just took it out. He said she could come back during
winter and he could put it back in.

Is this okay to do this to a car? We live here in Houston, and it gets
pretty hot and humid. Winters are pretty mild--the temperature hitting
below freezing shuts the whole city down...

Just asking for opinions...

 

In a modern car that is computer controlled based on information that
comes from sensors this is especially not a good idea. I would have
to think that it would be running in default (open-loop) without the
thermostat keeping temperatures within design parameters.

But, that's just my opinion, and I'm not a licensed mechanic.

Ken

 

They claim to have checked the sensors with their computers... I wished
I had taken some auto-mechanics class in high school...

 

Like I say, it's unlikely that all 3 sensors are bad, and even if they were,
that replacement price is excessive. I'd take it somewhere else.

 

I've read all the comments you've received. I don't know if I agree with
any of them. I will however, share my experience with you. First, I am not
a car guru. I had the SAME work completed as your shop identified for the
SAME price. The only difference is they replaced the thermostat. The
problem is gone. The work was done by a neighborhood garage in a suburb near
Philadelphia PA. I've had other work performed here with satisfactory
results. Your call.