Overheating E46 318i 2002

[marius.fourie]

My E46 318i 2002 overheats while I drive. The gauge goes from normal to red-light-on in about 30 seconds. It will then go back to normal operating temperature just as fast after a short while. What could that be? It happened about 6 times over a 50 km trip. The 1st time was after about 5 km.

 

[Fuzzy]

Can be an air lock, temp sensor switch, faulty waterpump. You need to feel whether top and bottom waterpipes are getting warm. Thermostat could be stuck. Headgasket even.

 

[crispy boss]

these cars have a habit of popping head gaskets!

 

[happynoodleboy]

I just spent R16000 getting this sorted on my 2003 325i.
Car was doing this from when I bought it about 2 years ago. Every 3 or 4 months this would happen. Had to top up water once a week.

Had the car at numerous people, replaced everything from the radiator cap to the water pump.

Finally a month ago the inevitable happened.
Car overheated again, lost all power.
Thought the head was cracked.
The guy who does my services found an older gentleman who specialises in BMW. He used to be an engineer with them. Now works from his home.
Had the car for 30 mins and phoned me.
The pipes feeding water into the head were all cracked right up against the head. No wonder I could never find any water. It evaporated as it was leaking.
Plus the plastic pipes running under the head were fubar.
Luckily for me the head was fine.
The head bolts stretched when they got hot.
So after a head recon, new bolts, helicoils, new water pump car is back.

Sent from my GT-N7100 a long time ago and far, far away.....

 

[racing snake]

sounds like a head gasket, common fault on these models