How trustworthy is the Temperature Gauge (far right dashboard) on 2004 325I E46 engine
Our mechanic says that these temperature gauges on the German cars are not always do what they suppose do - I have a hard time believing this.. Any thoughts on this?
The temp garage is buffered, 75C 115C, so within that temp range the gauge should read at the 12:00 position. Anything lower after a 5 minute drive in normal temps means the thermostat is bad. Anything higher, you should shut the car off and have it towed. Running any higher will overheat and damage the heads and maybe cracking the block. I assume you have the car at a BMW independent garage?
Tom: the gauge was at 12:00 position, it did not move while driving with the radiator/coolant warning light on. I drove total about 20 miles with the warning light on and then shut off the engine, heard some sort of fan running (not horribly laud but not very quiet either)which after 5 min it went off. I opened the hood, I saw water moisture and some was dripping down from the material that is mounted to the underneath of the hood. Clearly there was water evaporation going on... any guesses what could be going on? Yes, it is at independent BMW mechanic...
ok, good, sounds like you sprung a leak. could be a hose, thermostat, water pump or the expansion tank or radiator. Water on the underside of the hood means it was flung around by the fan. the noise you heard was probably the electric fan in front of the radiator if you have an automatic. that was on trying to cool the car. Your probably fine with the engine, just get the proper parts replaced and new coolant in it. You can't just replace one part of the system and hope it hold together. All the parts are equally old. Been there done that.
Tom: what are the proper parts to replace? I am very happy to follow your advice..
Copy the link into your web browser I posted above, it describes what you need to replace.
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