Revice

Forum Friends! My 92 190e starting getting hot on me while driving the other day. I also noticed a "boiling" sound coming from the hood, after I turned it off. I assumed it was the thermostat; I replaced the thermostat thinking that might solve my problem.

After the thermostat was replaced, I let it idle for like 20 minutes and noticed it was beginning to run hot again. The temp gauge was goin up pretty fast. Then when I turned it off, I heard that boiling sound coming from the radiator area....Any advice for me? Appreciate the help.

Jim Banville

Check oil to see if it is milky (water in oil from headgasket). Check color of coolant to see if it is brown (oil in coolant from headgasket). If those check OK, the first thing I'd replace would be the engine's fan clutch.

reubengeg

Recheck the thermostat. Take the thermostat out and test it. Put it in a pot of water on your stove and get the water heated up to a boil. Pull the thermostat out of the water with some tongs. If the thermostat is open it works. If it does not open then you have a defective thermostat.
If thermostat is good, I would try running the car without the thermostat to see what happens. If the water in the radiator boils again it is most likely the water pump. If you have a 6 cylinder good luck. Changing the water pump is an all day job. Changing a 4 cyl water pump is much easier. Good luck.
reubengeg

StruminJ

Did you check if the aux fan is working? It should kick in at 100c and cool everything down then go off (automatically). If the fan is not kicking in, it's likely the temp sensor (on the water pump) or the magnet (on the fan shaft).

If the fan isn't running, before you replace the magnet, you can manually connect the aux fan by pulling two connectors and putting a 10A fuse to connect them. (I can take pics and show you how).

Hope this helps.

z168

that almost 100% guarantees overheat if you do this

Ericthenorse

removing the thermostat will NOT cause it to overheat.... The thermostat restricts flow at low temperatures to aid in your motor warming up faster. When temperature is reached, it opens to allow flow. With the thermostat removed, it will cool just fine(possibly better without the restriction), but your motor will take longer to warm up.....

Aside from checking the fan, and temp sensor, I have another one... If you have a verry small leak between one of the cylinders and the watter jacket, it will sometimes cause compression from the motor to leak into the cooling system.... This can cause mysterious overheating by raising the pressure... Remove your coolant cap, and start the motor... Look for the water level rising... from air being pumped in..... On my Jetta, when I started the motor, watter came shooting out of the coolant bottle...

DarkCreep

LOL I got the same problem on my 190E.

1999 Eclipse GSX here I come!