Technical Engine Coolant Light keep coming on. Help?

[ickleric]

I have a W Reg (2000) 1.2 Fiat Punto. In the last couple of days the engine coolant warning lights keeps coming on. I have checked the water and that seems ok, checked the oil level that was fine. Under the oil cap it seems okay, doesn't look like its leaking water in the oil. The oil cap itself looked a bit gooey, but not inside i don't think. It comes on after using it for around 10-15 minutes. If i put the heaters full, it just blows out cool air. I have recently had the head gasket fixed in the last 6 months. Unfortunatly these are the same signs i had when the head gasket went. Also something different this time, is when you stop at the traffic lights you can hear the engine reving funny. It doesn't just idol like normal, it seems to rev very eratically.

Any ideas? (please don't say head gasket)

 

[The Sultan]

sounds like your head gasket is going again take it to were you had it done and simply tell them it's over heating and running rough and let them do the rest if it is surely they should fix it as they did it

when the combustion gasses blow into the coolant they collect in the back of the block and if there is to much off them they cause the over heating and loss of your heater

does your heater make gurgling noises as well

there is a possibility the garage that did your head gasket didn't get the head skimmed and this has happened as a result

incidentally the oil and water does not tend to mix on fiat fire engines when the hg goes due to the positioning of them in the head I rarely see any gunk under the cap

 

[Punto.Power]

I dont think its your head gasket, sounds to me that you have a faulty thermostat, they only cost like £14 and take 15mins to fit but i wouldint keep driving it while its overheating cause if your HG hasnt gone it might go, if you keep driving it like that.

 

[ickleric]

Just started the car, had it running for about 2-3 minutes with heaters on full. The radiator fan didn't kick in at all, would you expect it to kick in after this amount of time? If so does that point to the thermostat?

 

[Punto.Power]

Should run it at least 5 or 10mins before the fan should come on, but the heaters blowing cold air when set to warm, i would say its either the thermostat but sometimes as well they can cause the fan to act weird or the HG but thermostat is the cheapest option first.

 

[ickleric]

UPDATE:

Right i have just had the car running for about 10-15 minutes. After about 5 minutes or so the radiator fan DID kick in, however the ENGINE COOLANT IS TOO HOT light still came on again. So i checked the hose that goes to the radiator and the one that goes to the top right hand side of the radiator got HOT. I checked the hose that goes to the bottom left hand side of the radiator and that didn't get hot. Is that correct for those two pipes? Also not sure if this is connected but i noticed a small piece of thin flex pipe hanging loose underneath the battery (not sure what it was connected too.) Any ideas what that is?

Any ideas? Or what to check next?

 

[D4nny8oy]

The heater matrix isn't fed from the thermostat, it's directly off the head/water pump- thus ruling the thermostat out of the question, especially if the top hose gets hot. If the heater is cold it's full of air, and if the engine is overheating it sounds like there's an air-lock somewhere.

With the engine off, fill the reservoir to the brim. Open the bleed screw on the heater pipes and wait until only coolant comes out (keep topping up the coolant) then close the screw.
Now open the screw on top of the rad (passenger side) let all the air out, and the coolant level drop down to it's level then close. Start the engine and let it warm-up, opening the bleed screws a little now and again to remove any trapped air- put the heater on "hot" so you can feel when it starts working again. Hopefully at the end the fan will kick in and it shouldn't be overheating.

If it does it again, it suggests that combustion gases are leaking past the head gasket still (faulty repair).

 

[ickleric]

GOOD NEWS:

I think i've fixed it now, i bleed the radiotor whilst filling it up with coolant. Now the heaters blow out hot air, and also the light hasn't come on at all.

So thanks for all your help everyone.