Wrx overheating
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From: Dudley, England
Wrx overheating
Hi, need help folks!
sorry, I know it’s a common post but looking for some advice specific to my symptoms. I’ll try and keep it brief...
i have 03 wrx Impreza overheating, fan in car blows hot, it only overheats when stationary or stop start driving and cools down when I get to give it some gas. I have tried to burp coolant several times but it’s still happening in rush hour traffic. Oil temp says normal or less than 100deg but coolant will pass 2/3. Rad fans come on when warm, top rad pipes hot bottom pipes cold.
headgasket? - no oil in coolant and no coolant in oil, car drives fine other than overheating and no white smoke from exhaust...
Any thoughts on what it could be would be greatly appreciated.
sorry, I know it’s a common post but looking for some advice specific to my symptoms. I’ll try and keep it brief...
i have 03 wrx Impreza overheating, fan in car blows hot, it only overheats when stationary or stop start driving and cools down when I get to give it some gas. I have tried to burp coolant several times but it’s still happening in rush hour traffic. Oil temp says normal or less than 100deg but coolant will pass 2/3. Rad fans come on when warm, top rad pipes hot bottom pipes cold.
headgasket? - no oil in coolant and no coolant in oil, car drives fine other than overheating and no white smoke from exhaust...
Any thoughts on what it could be would be greatly appreciated.
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From: Dudley, England
Thanks guys I’ll Gary burping again and test the thermostat - are they common to fail?
in not I guess sniff test time ��
if if it was thermostat why does it cool when in flowing traffic then stop and overheat when stationary? Surely the hotter it gets the more open the stat should be?
in not I guess sniff test time ��
if if it was thermostat why does it cool when in flowing traffic then stop and overheat when stationary? Surely the hotter it gets the more open the stat should be?
Last edited by IVIike; Jan 18, 2019 at 08:41 AM.
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From: north east
over the years i have only ever seen 1 or 2 failed T/stats in the open position.............
most commonly they fail and jam shut but in this case that would mean high temps all of the time, sounds more like the fans aren't working??
most commonly they fail and jam shut but in this case that would mean high temps all of the time, sounds more like the fans aren't working??
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From: Newtownards - Northern Ireland
Coolant leak. I still haven't got my samco hoses on but originally my top radiator hose clip snapped so cut back top hose and reclamped.
A few times my temp started to climb went stationary but not when driving, then a few days later once I parked up I got the dreaded "under bonnet steam" found that top clip had worked itself slight loose again retightened and top up coolant and has been fine since
A few times my temp started to climb went stationary but not when driving, then a few days later once I parked up I got the dreaded "under bonnet steam" found that top clip had worked itself slight loose again retightened and top up coolant and has been fine since
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From: Dudley, England
Thanks for the info guys!
Please do do keep it coming!
must admit stockcar I didn’t suspect thermo as it’s a basic bit of kit.
intrestingly I burped again today, got it to normal running temp the put cap bk on and did a quick round the block, as the heating was on it didn’t get past normal running temp but fans didn’t come on! So connected the test plugs under the steering wheel and fans did function albeit the one sounded like it was catching on something I presumed a leaf as I couldn’t see anything and it wasn’t too loud.
also, I confess, I do think I have a small coolant leak on the front somewhere but it’s minor and as I’m keeping the system full and burping I wouldn’t have thought this could be the issue? If it is and I’m a idiot, please feel free to say so but if so can you explain how a slow leak can cause overheating in a full system?
im not mechanically minded but does this indicate anything significant? I’m not sure when the fans should come on? but I think I’m going to get it near to the 2/3 mark tonight and check if they are on then or not...
will keep ya posted, thanks again!
Please do do keep it coming!
must admit stockcar I didn’t suspect thermo as it’s a basic bit of kit.
intrestingly I burped again today, got it to normal running temp the put cap bk on and did a quick round the block, as the heating was on it didn’t get past normal running temp but fans didn’t come on! So connected the test plugs under the steering wheel and fans did function albeit the one sounded like it was catching on something I presumed a leaf as I couldn’t see anything and it wasn’t too loud.
also, I confess, I do think I have a small coolant leak on the front somewhere but it’s minor and as I’m keeping the system full and burping I wouldn’t have thought this could be the issue? If it is and I’m a idiot, please feel free to say so but if so can you explain how a slow leak can cause overheating in a full system?
im not mechanically minded but does this indicate anything significant? I’m not sure when the fans should come on? but I think I’m going to get it near to the 2/3 mark tonight and check if they are on then or not...
will keep ya posted, thanks again!
Last edited by IVIike; Jan 18, 2019 at 06:10 PM.
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From: P1234x
Fan might be catching on the top rad hose under higher revs will leave a small hole we’re you can’t see
usually happens if top rad hose isnt put on correctly check near bend area
will only squirt coolant wen under pressure
usually happens if top rad hose isnt put on correctly check near bend area
will only squirt coolant wen under pressure
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From: Dudley, England
Thx Zany, Gave it a quick run, fans do come on but that tick noise is still there driver side under the air intake I think. I’m gunna take it off in the daylight n have rummage. Tired running my hand along the top pipe but couldn’t feel the fan catching it / me.
might call out the aa too for the mobile sniff test
propa love hate relationship with this scooby business
watch this space lol
might call out the aa too for the mobile sniff test
propa love hate relationship with this scooby business
watch this space lol
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Maybe pjarvis, I think the pump is down that drivers side of the car, perhaps that’s what’s making the noise. Had cam belt done bout 2 months ago, I hear you should change them together (belt n pump) but i didn’t think it meant it would pack up so soon after if It is that.
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pumps in general terms dont simply fail and its simply 'internet nonsense' to change the W/pump & belt on a Subaru..............
if its was a VAG, Vauxhall or whatever then you would be correct
your system leak will certainly be the culprit or a heavy contributor so this need solved first and ensure the system is airtight and you will be inducing air locks, etc.
if its was a VAG, Vauxhall or whatever then you would be correct
your system leak will certainly be the culprit or a heavy contributor so this need solved first and ensure the system is airtight and you will be inducing air locks, etc.
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Thx stockcar, that’s good to hear, the cam was done by a reputable specialist I woundnt name cuz I don’t want people thinking they have done a bad job. At the end of the day it’s an old car so I guess things like this will arise. I’ll try n find it myself Later today and if not it’s off to the garage where a proper mechanic can inspect it
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Well it’s not the fan catching, the fan was hitting one of the wires powering the fan so I have tucked it out of the way. Crawled on the floor and it looks like most coolant is on the passenger side of the front. I’m lost, think I need to get it on the ramps...
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Had aa out today, didn’t sniff test but said he didn’t think it was headgasget as no mixing and runs too smooth. Scanned engine bay with thermo cam when overheating and nothing was over 92 n all the pipes n rad looked hot so it’s all circulating. Guage in car was showing 2/3 so he thinks it’s temp sensor knackered. Does any one know what the guage represents on a thermometer? - my norm running temp is just below 1/2 so I guess that’s 90 odd?
Also found error code P0483 - which is a fan rationality error, but I think that’s only on cuz the ecu is telling em to stay on due to the faulty sensor?
in the end agreed i should get a second opinion from a specialist...
good news i guess
Also found error code P0483 - which is a fan rationality error, but I think that’s only on cuz the ecu is telling em to stay on due to the faulty sensor?
in the end agreed i should get a second opinion from a specialist...
good news i guess
Temp sensor is basically:
Below temp threshold
At temp threshold
Above temp threshold
There is no way to ascertain what temp it is once it goes above the normal operating range indicator, just below 1/2, without fitting a proper sensor and gauge.
Below temp threshold
At temp threshold
Above temp threshold
There is no way to ascertain what temp it is once it goes above the normal operating range indicator, just below 1/2, without fitting a proper sensor and gauge.
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I have neglected to mention when aa fella plugged in his ecu reader, he said when hottest part of car was 92 from thermo Scan, but the ecu was reading 108 coolant temp. Can any one confirm if this points at coolant temp sensor?
if so I hear there are 2, do I change both or just one, which one? Argh!
i hear temps are:
93 - normal or at temp (just below half on guage)
98 - hot 2/3
107 - death time, I would imagine this is H on the stock guage
if so I hear there are 2, do I change both or just one, which one? Argh!
i hear temps are:
93 - normal or at temp (just below half on guage)
98 - hot 2/3
107 - death time, I would imagine this is H on the stock guage
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I have neglected to mention when aa fella plugged in his ecu reader, he said when hottest part of car was 92 from thermo Scan, but the ecu was reading 108 coolant temp. Can any one confirm if this points at coolant temp sensor?
if so I hear there are 2, do I change both or just one, which one? Argh!
if so I hear there are 2, do I change both or just one, which one? Argh!
Always use the copper sealing washer, not thread tape, as the gauge sensor uses the body as an earth path.
marked as 22630 below
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Not necessarily, just making sure you have the correct info on the item.
Always difficult to diagnose.
I went through a similar process until I confirmed it was HG failure - sniff test didn't show anything amiss.
With coolant full and expansion bottle at the correct level, what happens if you take it for a good blast on boost - does the expansion tank level rise more than expected/overflow?
Also when engine cools (say overnight) after a run does the expansion tank level drop or stay at the same "hot" level?
If you've got a leak on the passenger side of the engine look at thermostat housing, bottom hose/rad. Given it's age it could also be the cross bay coolant pipe from the oil filter modine to the water pump.
Always difficult to diagnose.
I went through a similar process until I confirmed it was HG failure - sniff test didn't show anything amiss.
With coolant full and expansion bottle at the correct level, what happens if you take it for a good blast on boost - does the expansion tank level rise more than expected/overflow?
Also when engine cools (say overnight) after a run does the expansion tank level drop or stay at the same "hot" level?
If you've got a leak on the passenger side of the engine look at thermostat housing, bottom hose/rad. Given it's age it could also be the cross bay coolant pipe from the oil filter modine to the water pump.
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Thx Don,
did is a blast on way home overflow tank went up about 1/2 pint, kept temp in tolerance with heating on. I guess that’s normal and it will drop down to less than it was in the morn as I’m topping by bout half pint every other week.
when your hg went did you have other symptoms like smokey exhaust, running rough or mixing oil n coolant?
i guess it’s trial n error now, coolant leak n stat then sensor n then, I dunno, take up religion...
did is a blast on way home overflow tank went up about 1/2 pint, kept temp in tolerance with heating on. I guess that’s normal and it will drop down to less than it was in the morn as I’m topping by bout half pint every other week.
when your hg went did you have other symptoms like smokey exhaust, running rough or mixing oil n coolant?
i guess it’s trial n error now, coolant leak n stat then sensor n then, I dunno, take up religion...
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None of the above and as said sniff test didn't show anything either.
What did happen is that coolant level sometimes didn't drop in the expansion tank as engine cooled overnight, leaving the header tank low with air in the system.
Finally confirmed after a non stop return trip from Castle Combe to Harpenden and the expansion tank was overflowing and bubbling away.
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Ah I see, be nice if these things were easier to diagnose, got sensor n stat on delivery now so hopefully can sort them the weekend. Will keep posting on progress in hope the thread can aid another poor suffering soul!
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Fixed! Was thermostat, looks like the old one was a cheap aftermarket one, replace and all is gd now.
10 points to the shreksta
thanks all for your advice, was really appreciated!
10 points to the shreksta
thanks all for your advice, was really appreciated!
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