Hey whats up I have been troubleshooting a problem with my 2004 ralliart overheating for some time now. I have changed the following parts thermostats, FCU, Water Pump, Timing belt and Coolant temp sensor. The problem is the car overheats if the heat is on and sometimes it just overheats anyways. On the freeway at about 75mph the car still runs hot. The fans do come on but they turn on and off never consistent. Then again sometimes the car works just fine I am confused and the dealership has no clue what to do wasted money. There is one thing that I noticed is that the bottom hose is cold most of the time and the top hose is hot. I don’t have any more ideas please help if I don’t fix soon I know I will be doing a head gasket thanks.


Mods:
SRI
RRM under Pulley
RRM flywheel

 

To begin with, how can you tell its overheating? Is the water temp gauge reading high or what?

 

if the vehicle's moving, it definitely shouldn't be overheating...who replaced the thermostat? and water pump?


there's only a few things that will cause it to overheat. but yes, a picture of your temp gauge would helpful.

 

The temp gauge reads high but no coolant overflowing are anything else but you can smell coolant like its hot.

 

Hmm, you've thrown big bucks at it so far on all the "right parts" and even the dealership doesn't know what to do about the perceived problem (which is an odd thing)

Next step is to spend $50 for a proper water or oil temp gauge and install it. Report back here what the exact temp reading is when you smell hot coolant. Then we can tell if there really is a problem or not.

 

Do you have to add coolant regularly ?
If you remove the radiator cap and run the engine while it's at its operating temperature, do you see big bubbles coming up through the coolant ?
Normal temperature gauge reading for our cars is when the needle is barely under half way.
Did you try running with no thermostat at all ?

 

I did all the work myself except for the coolant temp sensor which the dealership did. I plan to try without thermostat this weekend has anyone tried an 170 degrees thermostat. I have been thinking about it but am no sure I dont just want to keep throwing money at the problem. I picked up some flushing kit to make sure the radiator is not clogged too.

 

the only thing I can think of is a clog, or contamination...and if you smell burnt coolant, you may have a small leak as well.


what thermostat did you install?

 

Motorad thermostat 180 degrees but this is the 3rd one I am thinking of getting a Dealership thermostat next.

 

I would definitely try OEM, and make sure you do a full flush and bleed (burp some call it) of the system. But then again this is the 3rd thermostat? Also make sure the rad is not like super dirty and has good air flow on the outside, cause at 75mph, the fans shouldn't even need to come on, you should have more than enough cooling.

 

 

yeah, that's ****ed...if it's running that hot all the time I would think something would have blown by now.

 

Yup. Check under the oil cap. Does it look like oil or milky? Blowing smoke?

I'd for now take out the thermostat.

 

Well thanks for all your help it died last night with no CEL's so I am guessing head gasket now for sure. I said I wasnt going to do it but I am going to jump on it today should I have the head shaved now are just put it back together?

 

if the timing belt was not damaged or contaminated by oil or coolant you can re-use it, just make sure you mark the direction before removal. if you're pulling the head, it's not a bad idea to have a valve job done, and replace guides if needed, while you're getting it decked. Make sure your head bolts are serviceable (within spec) before reusing them, if not you'll need to replace them as well. and don't forget new valve stem and spark plug seals