WHY is my car overheating only while moving?

Question

One cold day this winter I thought I blew up my car. Drove it down the road 5 miles it overheated and cut off.I had the block checked out and it was fine. I have found no leaks. The fan is working. and i replaced the Radiator cap. And flushed the motor, and replace the thermostat.

Now I wanted to test drive it to make sure everything was okay I let the car idle in the driveway for over 45 minutes, checking the tempter and looking for leaks. THere were no leaks and the cars tempter hoovered right around the middle THinking I was safe went for a ride. I drove around for 30 minutes and still fine. stopped at a light he temper went all the way up. I let it cool off. got home, flushed again. tested it again in the yard for half an hour with no problems. went to drive it around the block i only made it a mile before it overheated this time? I need help. Starting a new job in four days and i have got to get this fixed/

Answer 1

It, my car, the car, We Need the vehicle information! (year, make, model) in order to be able to properly diagnose a cooling issue! This sounds like a restricted radiator, but like I said, without the vehicle information this is just added to the other guesses!

Answer 2

I had this problem where it would run okay for about 20 miles but on the return trip it would get hot--nearly overheating. The problem was inadequate flow. I replaced the radiator and that solved the problem. You can get a handle on this by running the engine with the cap off until it is warm enough to open the thermostat. Water is rushing by. When you accelerate the engine, the ater should not spout up out of the neck. I had the radiator off and water flushing through it--it looked good but was inadequate flow nonetheless.

In your case it could also be a leaking head gasket but if so you might see white smoke, or evidence of water in the oil, or poor running. The timing can also cause overheating if wrong but should not be wrong unless it was changed.

Answer 3

you never mentioned what kind of vehicle, here are 2 possibilities. # 1 it could have air locked in the cooling system,first look close around the top of the engine at the thermostat housing and see if there is a bleeder valve to release the air out of the cooling system it will look just like the bleeder valve on the brakes,it is a 10mm. Start the engine and let it heat up or even drive it and let it get hot,let the car run and then turn the bleeder valve counter clockwise very slowly until a steady stream of water is coming through remove the rad cap and fill it and then tighten the bleeder valve. # 2 possible clogged up radiator or water pump.,,,,,

Answer 4

If only people with no idea what they are talking about would quit giving advice that only makes things more expensive and does not solve the problem.

A car that has all the symptoms you give has two possible problems.

#1 the radiator is plugged and needs cleaned. Flushing is a waste it must go to a radiator shop.

#2 There is no anti freeze in the system.

Answer 5

You most likely have a cracked head or blown head gasket. Bad news.

What is the Year, Make and Model of your car? I will be able to tell you if repairing it will be worth the money, or if you should buy a new car.

Answer 6

im guessing restriction or water pump could also be boiling coolent due to wrong mixture,old or bad rad cap

Answer 7

your water pump is shot, probably bad fins, they wear off after time, replace it soon, and change your oil any time your car overheats, it boils the oil and robs it of viscosity

Answer 8

your water pump may be bad. you did not mention what kind of car you have this may help some people who had this problem before help you.