My Car is Over Heating and My Auto Mechanic Can’t Fix it

Reader Question Dear Austin,

Thank you for your reading this email. I do appreciate your help. I have overheating problems with my car, but I got confused information from different mechanics.

One month ago, I found overheating problems and coolant lost. The dealer first said something was wrong with the thermostat. Then he said no, but there may be something wrong with the water pump. Afterward he said no again. Finally, he concluded that there may be something wrong with the head gasket. However, I could not see oil in the radiator or water in the oil.

I went to another mechanic. He found the fan had failed. He changed the sensor, and my car worked well since then. However recently, I randomly encountered failure starting the engine on three different occassions. I had to restart my car for a second time after reversing the car in order to get out of the parking lot. After restarting the car, it worked very well. What kind of problem it is?

At the same time, the car started overheating again. I went to a third mechanic. He checked my engine with a computerized engine analysis, and concluded that there is excess pressure in the cooling system. He checked for exhaust fumes in the radiator, and the chemical test was positive. He said it should not be positive. This mechanic can only imply that there may be something wrong with the head gasket, but he recommended that I return to the dealer for a check.

I added more water and coolant to my reservoir two days ago. I noticed there are coolant puddles on the ground under my car. There are also some water puddles. I tried to drive yesterday, but the temperature was almost close to the maximum after 5 or 6 minutes at 35 MPH. By the way, I only saw white gas from the car once at idle.

I could not tell the smell. Additionally, my air conditioner seemed to be related with such overheating problems. It sometimes works but sometimes not, especially on the freeway.

Do I really need a new head gasket? It really costs a lot of money.

Looking forward to your advice.

Lijun

Hey Lijun
Have you read my article on overheating?
Engine overheating

The first thing you should do is get a cooling system pressure test performed on the cooling system. If you have coolant on the ground, that is a good sign. It tells me you have an external water leak, and the pressure test will find this leak.

A head gasket leak is internal, and you will see coolant in the oil, on the tips of the spark plugs, and white smoke out the tailpipe. You may have a head gasket leak as well, but let’s fix the obvious, less expensive problem first and go from there.

The dying problem, depending on what kind of car this is, might be a dirty throttle body and idle speed control motor, which your mechanic will know how to clean. This repair is cheap and easy to do and is a good guess.

Let me know what you find out,

Blessings,
Austin C. Davis