Q: Hot at idle and low when driving never stays in middle

asked by on

Just replaced 3 freeze plugs and thermostat and radiator cap. Car won't hold stedy temp I have no leaks now and no heat maybe 2 min of heat then cool air.

My car has 167000 miles.
My car has an automatic transmission.

Hi. This sounds like the water pump is not circulating the antifreeze in the engine. When a water pump stops circulating the antifreeze as well as it should the car tends to run hot when it is at idle and cooler when you are moving because you increase the engine speed while moving causing the water pump to increase its speed. Another possibility is that the radiator is clogged and causing the flow of coolant to be restricted. I suggest you having a certified technician from YourMechanic come and diagnose your cars overheating condition to avoid any necessary repairs.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Hot at idle and low when driving never stays in middle

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Still overheating after replacing thermostat and radiator.

Hello, thanks for writing in. I suggest having the engine diagnosed by a mechanic to see if the cooling fans are working like they should, and if they have overheated, then see if engine head gasket is blown. I also...

Q: How to fix squealing power steering

Hello....This could be a dry or worn out ball bearing assembly of which there are quite a few (alternator, A/C, idler pulleys, etc) or it could be a belt alignment, belt age, or belt tension issue. YourMechanic can isolate these...

Q: Only when it's really hot outside the temperature gauge reaches almost about less then half way. Car won't start up again till coo

There may be 2 issues to deal with here. The inability of the engine to reach "normal operating temperature" (always the center of the gauge), indicates either a weak or failed thermostat, or a failed coolant temperature sending unit/coolant temp...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...