Water Temp Problem.. Help Please

[WRX Haz]

Hi Folks,

I hope someone can help me. I have a strange problem with my WRX RA, car was running fine then the other day I noticed the heater was running cool even tho the temp was on hot, I had just driven 15 miles. I checked the temp gauge on dash and noticed it was down at the bottom indicating cold, so I have another temp gauge mounted in centre of dash and this was reading 30 deg.

Checked the water level and its fine, no loss of water at all. Basically if I warm the car up for 15 mins before I use it all the temps are normal, once i drive the car all temps drop to the bottom... mega confused. . can anyone help please?

Thanks

Haz

[Kenny.S]

Sounds like the thermostat is jammed open.

You'll get a replacement one from your local dealer no probs, not that expensive either and it's relatively easy to change, wee bit fiddly to get to but it shouldnt take more than 30-45 mins from start to finish.

[RS Grant]

IIRC someone told me that if you take the stat out and put it in a bowl of hot water.. it should pop, if it doesnt pop, its knackered.

Cheers,

Grant

[Kenny.S]

By the sounds of it though it's already stuck open

[RS Grant]

Haha, this is true...

Cheers,

Grant

[iain_ogston]

I had exactly the same problem on my MR2 - the temp guage just wouldn't go past C unless I was stuck in traffic.

Was the thermostat - when it came out it was in two pieces!! (should be a one piece item lol)

[WRX Haz]

Thanks guys, will try get a look at it tonight hopefully I can get a replacement by the wknd.

[st3ph3n]

Fit one of the good replacements if you can - zerosports cool thermo etc.

[dipsy]

I am sure Awd sell the zero sports cool thermostat

[AlanG]

Fit one of the good replacements if you can - zerosports cool thermo etc.

why is that?

[euan_r]

if cars not modded much for power i wouldnt bother with upgraded thermo.

mine went on my old car and replaced with fancy one. when out a spirited drive the temp gauge would fall to hardly registering when there was clear road. lower water temp would mean lower oil temp as well. there is sure to be an minimum oil temp for keeping things right. i could easily be taking gash but thats the way i see it.

cooling is important if you are stressing engine more.

or if you want one i am lead to believe alan is the man to ask about what size drill bit you take to a std one.

[RS Grant]

I had TRD thermostat on my pretty highly modified Celica GT4 and I saw the same thing happen as Euan, on the dual carriageway my temp gauge would sit on the minimum marker.. and once tooling around town/more spirited twisties then it would creep back up.

Dont know if it was cooling down to the point of being unsafe to boost it though... its not quite that extreme I dont think. Haha, I hope not, I sold that Celica in good faith!!

Cheers,

Grant

[st3ph3n]

why is that?

I remember our wee chat now Alan. Fit a standard one with a simple modification done to it then?

[thewelsho]

I remember our wee chat now Alan. Fit a standard one with a simple modification done to it then?

tell me more about this please!!!!!

[AlanG]

The only difference between the Zerosports stat and the std one is that the Zerosports opens at a lower temp than the std thermostat, 71 degrees as against 78.

My experience told me that taking a std 'stat, removing the toggle pin and drilling the hole to 3/16" gives similar result on the road. Doing it this way also means you've also got circulation all the time and reduces the chance of air locks. The slight additional benefit is that at least some water still circulates if your 'stat sticks shut stopping the water from boiling off and then creating airlocks or possible head gasket issues.

Drilling the hole bigger or drilling a 2nd or 3rd hole will give you the same symptoms as the OP is experiencing i.e. cold water temps when cruising.

Edited April 25, 2008 by AlanG

[AlanG]

mine went on my old car and replaced with fancy one. when out a spirited drive the temp gauge would fall to hardly registering when there was clear road. lower water temp would mean lower oil temp as well. there is sure to be an minimum oil temp for keeping things right. i could easily be taking gash but thats the way i see it.

cooling is important if you are stressing engine more.

You're right Euan. Water temps can rise pretty quickly but oil takes a good bit longer. You might get water temps up in a short time from cold start, but oil will take considerably longer. Ideally you want to get the oil up to about 80 degrees before giving it some stick, but not many have oil temp gauges.

[thewelsho]

You're right Euan. Water temps can rise pretty quickly but oil takes a good bit longer. You might get water temps up in a short time from cold start, but oil will take considerably longer. Ideally you want to get the oil up to about 80 degrees before giving it some stick, but not many have oil temp gauges.

Takes a wee while to get it to that temp, but thanks for posting that because I often wondered. My car seems to run at 97 during normal use... is that too high d'you think?

Don't spose there are any pics/tutorials to help with the removal/drilling of the thermostat? I wouldn't know the first place to look.

[colin_ross]

Don't spose there are any pics/tutorials to help with the removal/drilling of the thermostat? I wouldn't know the first place to look.

I have an old "AlanG" modified one in my garage. It's yours if you want it.

[thewelsho]

I have an old "AlanG" modified one in my garage. It's yours if you want it.

Er OK! Even better. If I doesn't work out I can go back to the standard one. Will it do the MY06?

Cheers Colin

[AlanG]

"if it ain't broke, don't fix it"

[thewelsho]

"if it ain't broke, don't fix it"

Aye, I spose... but my oil temps, according to my gauge is running at near to 100 degrees. I know that oil and water temps are not the same thing obviously, but I was thinking that if I can get the temps down in another way, it might help overall - I dunno. I stand to be corrected and educated.

[AlanG]

If you're worried about oil temps, why don't you fit a thermostatically controlled oil cooler?

[thewelsho]

If you're worried about oil temps, why don't you fit a thermostatically controlled oil cooler?

I will in time, but funds do not permit at present just looking for ever little bit that might help in the meantime.

[AlanG]

FWIW Welsho, i never ran an oil cooler in my 2.5 in the 3 years i had it and never had an issue. If i tracked the car, that would probably change, but you're not allowed to track yours now, so err.. yeah...

[fai17]

FWIW Welsho, i never ran an oil cooler in my 2.5 in the 3 years i had it and never had an issue. If i tracked the car, that would probably change, but you're not allowed to track yours now, so err.. yeah...

touchy subject