Over heating

WRIVERA

MEMBER
MAZDA 626

I have a Mazda 626 LX/DX 1998 with 154,000 on it.
The problem I'm having is that at idle the tempeture stays normal, but once I drive it about 2 miles, it starts overheating and the heater inside starts blowing cold air. If I stop for 30 seconds, the temp. Starts dropping quickly, but as soon as I start driving again it goes back up.
What I have notice is that after I park the car and don't use it. It empties the water deposit but it has no leaks. I checked the radiadior and water flows fine, replaced thermostat (does it even without thermostat), replaced water pump, and it's driving me nuts! Any Idea?
Thanks. :(

1 Reply

ADU

MEMBER
15 POSTS

What does the heat gauge indicate?
How long have u run the engine at idle?

There are some simple things that you can do to better understand the problem.

1. Check coolant level regularly.

2. Check the caps on the filler and reservoir for any damage and if they are of the correct specification.

3.
i) Open the oil filler cap on the engine and look for white stuff. (Coolant vapors are leaking into the engine)
ii) Start the engine and look at the tail pipe for white vapors.
iii) Block test is a sure way of eliminating this to be the reason.

3. Check if your fans are switching ON and OFF. Start your car and wait for a few minutes. With your hood open listen for the fan.
Also, close the hood and drive your car with the windows open, do u hear the fans working.
As you are saying it is overheating, check if the fans are switching when the engine gets overheated.

Be careful not to overheat the engine too much as this could lead to a blown head gasket.

Please refer to my posting "Unexplained overheating problem" at the link below to see some more tests by Raazmatz.
https://www.2carpros.com/forum/unexplained-overheating-problem-vt23598.html