Temperature guage drops at idle


#1

I have a 2004 Honda Civic that has about 183,000 miles.
The problem is that when I start my car in the morning, the car never totally warms up when it’s cold outside (I live in VA), until I press the gas pedal and rev the engine. Until I press the gas pedal, the temperature gauge stays at cold, and the heater blows cool air. I’ve taken it to the dealer 12 times for the same issue, but they can never find the real problem. They flushed the A/C hoses and radiator, replaced the radiator cap, installed an upper hose, installed head gasket, water pump, and while there, the timing belt. They’ve also “burped” it numerous times. Also, when I have the heater on and fan on high, the temperature gauge drops as I’m going down a mountain and not pressing the gas pedal. After driving, and I stop, it also slowly drops while idling for about 5 - 10 min.

When it’s warmer outside, I don’t have any problems, because I don’t have the heater on.

This has been going on for about 1 1/2 years now, and it’s starting to get cooler again, so I need to get it fixed or sell it. I just don’t have it in me to sell/trade it and pass this problem to someone else and they have to start all over with trying to solve the problem.

Please help!!


#2

Replaced your thermostat?


#3
They flushed the A/C hoses and radiator, replaced the radiator cap, installed an upper hose, installed head gasket, water pump, and while there, the timing belt. They've also "burped" it numerous times.

Talk about getting the most you can from some one! Sounds like a classic case of the thermostat stuck open. Yet it looks like the dealer replaced everything else possible first. Are you sure the thermostat was not replaced at one time?


#4

OMG, please tell me you’re not serious. The dealer replaced the head gasket? How much did they make you pay for all that unnecessary work? When all it needed was probably a new thermostat, as others have said.

That’s why they’re called “stealerships.”


#5

No one will remember, but was the thermostat installed with the weep hole or pin “up”. This minimizes the need for “burping” and maximizes the completeness of the fill.

At this point, when the car is cold, remove the radiator cap and note the coolant level. I think the reason for intermittent heat is that the coolant level is (very) low so that the engine has to be turning faster than idle to get the coolant to circulate at all.

Not having the heater on does not solve the problem.

Was there evidence of the head gasket failure when the head came off the first time? After 1 1/2 years, the head (and block) are probably warped which caused the new gasket to fail.


#6

Yes…it has now had 3 thermostats!! The dealer burped it each time I had it there. When they changed the head gasket, they said the head was not warped.


#7

They did the compression test and said there were 3 little bubbles.


#8

I’ll check the coolant when I get home…After it sits a while. I’m at work now…sorry for the delays in replying. I told the dealer I’m not paying any more labor costs.


#9

I don’t know how the thermostat was installed…pin up or not.


#10

The radiator is full.


#11

My husband is going to flush the heater core this weekend, even though the dealer said it’s not clogged. He’s a also going to check the flap.