trackjunkie

Hey all, I'm thinking of getting a '94 E320 w/ 79k on it. The only thing holding me back is that the car runs rather hot. The temp needle reaches just shy of the 120 mark when just sitting in traffic. I took only a quick glance under the hood to investigate. Here's what I found: there is quite a bit of pressure in the overflow tank, the cooling fans don't have much of an effect on temp and the biggest tell tale for me is that of the three hoses going into the thermostat housing, only one has pressure. The other 2 are completely soft. Does this sound like a stuck thermostat to you guys? Hopefully it won't be too big of an issue. Thanks in advance...
-Tom
'95 M3 (track car/daily)
'94 Miata (track rat)

jean_pierre84

i got a 1994 E 320 coupe sportline and let me tell you that is a fine car. Good engine and a really fun ride. The problem may be caused by the heat sensor, its usual after 11 years. I don't think it could be something significant if you feel the car runs ok but just in case you wouldn't lose anything by checking it. And believe me, this is a great car

AMG_Eric

he has a m104 motor if its a 1993.

i would check:
the thermostat
the water pump
the radiator (maybe its clogged)
the heater core

keep in mind these engines do run hot especially if it is HOT outside. if it is cold outside they dont run that hot. if it is running hot and its say 70 or below outside you need to take your care in. if it gets too hot it will blow a head gasket.
to check to see if you have a blown headgasket which you might if you are getting back flow into the bottle do this:

1) remove radiator cap
2) turn on your car and warm it up
3) now step on the brake firmly
4) put the car in drive AND HOLD ONTO THE BRAKE
5) give the car gas and keep it that way while trying NOT to burn the tires off the rim

if the water starts shooting out of your overflow bottle you are the proud owner of a blown head gasket.

jeffreyli86

hey eric,
thanks for that guide... would do the check when i've got the chance

just want to make sure.. you remove the radiator cap, and the water would shoot out of the bottle (the one where you add coolant in?) if the gasket is blown?

thanks

AMG_Eric

yes and make sure you are loading up the engine. it wont do it at idle in neutral.

jeffreyli86

thanks once again..
but i thought, putting the car in Drive with both brakes and gas applied, would put strain on the tranny and maybe cause premature wear?
i did that quite a few times at the traffic lights just to get the quickest launch speed i have an underpowered car

AMG_Eric

you are only dong it for a few minute and to find out if you have a blow head gasket.

TheDoughboy

My car did the same thing a little while after I got it, I noticed it had an Aftermarket radiator cap. Replaced it with an OE one and temps are now fine. Idles all day with no overheating.

HTH,

Ron