endrop - for all your online needs

Technical Now WHAT!!! OVERHEATING?

Currently reading:
Technical Now WHAT!!! OVERHEATING?

jug said:
sometimes i wonder if it would be easier to buy a toyota :)
Click to expand...

You are absolutely right... But then again Toyotas are for old people, we'll get one when we're old!! Right?
 
haha, yeah when we're too old to read a haynes manual we'll have to get something reliable, then again by that time cars will probably be able to speak and tell you what the problem is. but if you asked a fiat what was wrong with it, it would just say 'how long have you got?' and then overload with dozens of fault codes.
 
Honda, Toyota, Nissan and Subaru... All great Japanese machinery... My uncle just got a new 2006 Subaru Laegacy Sport...It's 4WD and has a turbo... Now that's a car :worship:
 
4WD and a turbo is the minimum requirement of a real car. nothing else will do. i'd love an evo 5 or 6, but an impreza would keep me happy for a while. i've got a friend with an import type RA 2 door (same as P1 uk models) running at over 400bhp before he uses the nitrous. what a car, it scares me, he hits 140mph on sliproads joining a dual carriageway. i dont know how they're allowed on the roads!
 
:worship: Amen to that....
Anyways back to the subject of the post ;)
The mechanic guy filled the cooling system with water so I would test it these couple of days and if all is well then he'll put coolant on saturday... Fingers crossed:eek:
After fixing the relay of the fan and changing the thermostat and thouroughly cleaning the radiator from inside at a rad specialist (he told me it was very dirty)... Could it be something else? The water level doesn't drop at all, what else could it be? The only thing I haven't changed is the cooling temp sensor... What do you think?
So far so good.
 
if the temperature still gets up to the red after all that i cant think of much else it could be, possibly a weak water pump, or a slight blockage somewhere. who knows maybe its just the temp sensor is faulty and when your gauge reads red its only really half way. i hope the problem is fixed this time mate.
 
TheCROW said:
Hanes Manual says: "The fan motor can be tested by disconnecting it from the wiring loom, and connecting a 12V supply and an earth wire directly to it."

So I think this should answer your question :)
Just make sure the wire connected to the battery is actually conducting the current ie. Check the fuse and the wire itself for any abnormalities...
Also check the earth connection the other one.
Hope this helps.
Click to expand...

Took the fan out an tested it OK, so I think it's not being switched on. So I looked at the temperature sensor and measured the resistance, and it seems to work. But am still overheating when sitting in traffic. It seems the ECU isn't telling the fan to turn on. Taking it to FIAT sounds expensive. Any ideas anyone?
 
try replacing the relay with one from a scrapyard. should cost all of £2. failing that its time to get the multimeter out and check the relay's wiring.
 
jug said:
if the temperature still gets up to the red after all that i cant think of much else it could be, possibly a weak water pump, or a slight blockage somewhere. who knows maybe its just the temp sensor is faulty and when your gauge reads red its only really half way. i hope the problem is fixed this time mate.
Click to expand...

Hey Jug, it happened again today. Can you believe it?
On my way to work, the temp needle went up to the dot just below the red.
The fan was working and I touched the radiator, it was not hot. I could put my hand on it for as long as I wanted...
I noticed that the coolant wasn't boiling and it was not circulating, what I mean is that it's not going back into the expansion tank from the upper hose. I don't know if that's how it's supposed to be.
What do you reckon the problem might be? I have already changed thermostat, flushed radiator and bled, fan relay...
Could it be an intermittently week water pump or the coolant sensor?
How can I make sure? The car takes normal time to warm when first started in the morning and other than this there is no other noticeable strange behavior.
Come to think of it, I do hear a rattle-like noise coming from the cambelt area when the car is warm...
 
Last edited:
:eek: oh no not again!!!!!
this thread just wont die.

well if the radiator wasnt hot but the gauge was nearly on red, realistically there can only be 4 reasons;

thermostat not opening-
if the thermostat is new and this problem doesnt happen all the time it probably isnt the thermostat that is the problem. they dont stick once in a while, when they stick they tend to stick permanently causing you to overheat every time. but a stuck thermostat would mean the radiator stays cold when the engine overheats so it cant be ruled out, but as its new it is unlikely to be the cause.

water pump not circulating-
the water pump is also very unlikely to have an intermittent fault, its driven by a belt and either works or it doesnt. you would have the overheating every time if the pump was dying, not once in a while. the rattling around the cambelt area could be the waterpump. so i wouldn't rule it out as a cause, but its unlikely.

blockage-
a blockage would also not cause an occasional heating problem, it would be a constant noticable problem. unless this is the first sign of a new blockage (in which case you'll overheat every time from now on) i doubt its the cause. however a recent flush can cause blockages just as easily as it can remove them. dislodging a load of crap when flushing the system can then create a situation where the remaining crap in the cooling system is left to collect in one area casuing a new blockage. its possible, but unlikely. i dont recommend flushing the system again.

temp sensor-
i left this one till last because i've got a feeling its the likely suspect. the radiator was cold, the expansion tank didnt have a return supply of boiling water, basically no signs of overheating at all apart from the temp gauge. add to that the fact that you havent change the temp sensor and pretty much everything else has been looked at recently. its seems most likely to me. i'd change it, they are cheap and easy to do, and you've tried everything else so it has to be worth a try.

what do you think?
 
Thanks Jug for taking the time to reply.

I don't know what to think anymore, cos everything was changed and radiator was flushed, except for the temp sensor and the pump...

I'm not loosing coolant and the car drives fine.
What else can it be?
The noise in the cambelt area appears when the car is warm not when cold.
Although I have changed the cambelt and tensioners 10000KM ago.

Maybe I should try and change the temp sensor... Will I have to drain the whole cooling system again?
 
no, if you're quick when changing it you'll only lose a very small amount of coolant. then you can just bleed the cooling system using your favorite bleed screws and top up if neccessary. gotta be worth a try.

the rattling could mean a worn bearing in either the water pump, powersteering pump, alternator, oil pump, camshaft, crankshaft, tensioner, or it could mean either belt has been over tightened or is too loose. without hearing the noise for myself i cant be more specific.
 
I think that the noise is probably caused by a water or oil pump bearing I agree.

I just called the mechanic and he told me we'll change the coolant temp sensor and another sensor on the radiator... Haven't heard of that one. Any ideas?
 
You must log in or register to reply here.

Similar threads

V
Technical 1996 Fiat Bravo HGT overheating problem
Replies
12
Views
806
SS90
SS90
O
Technical Changed Springs now car pulls to the left
Replies
0
Views
985
Ozzy747
O
gihan798114
General What is this part called?
Replies
0
Views
1K
gihan798114
gihan798114
I
Technical What connector is this?
Replies
4
Views
1K
maniacbravo
maniacbravo
T
Technical New cutch fitted now problems
Replies
13
Views
2K
Adrian Bravo
Adrian Bravo
Back
Top