Please Help... Overheating. Temp Sensor or Head Gasket?

[drivebycar]

Hello,

Started her up this morning (very cold minus degrees probably), felt like something was holding it back when I pulled off. Got most of the way to work then oil and temp lights came on and steams was pouring out from under the bonnet.
Topped up the oil, let it cool down a bit then carried on. Same happened again so managed to get some water from someone and top it up.

Long story short every 2 miles I would have to stop to cool it down. Could not see any oil in the coolant, the first time it stopped there was a bit of light brown stuff on the oil filler cap, but was not present 2nd and 3rd times i stopped.

The temp sensor on the top of the dash display does not move normally. stays on nothing. However this morning it moved slightly into the white.

Any help would be very appreciated as this is a nightmare!!

[drivebycar]

bump. please help!
nice one 

[takethefifth]

It's overheating and badly. Was there a decent mix of antifreeze in your water?   The only time i've had those symptoms was a blown head gasket i'm afraid.

Where was the steam coming from? If its from the expansion tank you could try a new cap.

And you say you topped up the oil, the oil light is a pressure warning light not level, did you check the level of the oil and how was it?

[drivebycar]

It's overheating and badly. Was there a decent mix of antifreeze in your water?   The only time i've had those symptoms was a blown head gasket i'm afraid.

Where was the steam coming from? If its from the expansion tank you could try a new cap.

And you say you topped up the oil, the oil light is a pressure warning light not level, did you check the level of the oil and how was it?

Hi,
Not sure if there was a good amount of anti-freeze, have not changed it since i bought it a week or so ago. Steam was from the expansion tank, but its not the cap was definately over heating.
Oil level was a bit low, has a small leak, so topped it up.

[takethefifth]

Sounds like you're going to have fun with this one! 

The cap on the expansion tank has some kind of pressure valve in it, if this goes it will cause the water in the car to boil up at too low a temperature. Worth changing. I can't imagine anywhere else on the expansion tank the steam was coming out of?

The dash temp gauge staying low is normally a knackered thermostat but this causes the car to run cool, not overheat. Could be a combination of things...

Does your oil temp display work on the dash LCD? That will give you a good idea of if its really overheating or if its just the water system not sealing properly. Normal running temps will be anywhere from 90 to 110. Bear in mind the temp does not register (displays --) until it hits 50. Should take 15 mins or so to warm up.

[drivebycar]

Steam was just coming out of the top because the pressure got so much I guess.

The dash temp gauge never read anything till today so I will change the thermostat anyway.

Dont think the MFA comes up with the right numbers, always stuck on the same ones.

[JimR]

Did you notice if your coolant hoses were under alot of pressure? Sure sign of gasket failure.

[takethefifth]

I wouldn't touch the thermostat till you've figured out the cause of the overheating. No point throwing good money at it if its something more serious.

A sniff tester will tell you if you're getting exhaust gasses in your coolant (ie. headgasket failure). Most garages should be able to go this test for you at little money if you don't have the kit yourself.

I'd still change the expansion tank cap in case its gone. Worth doing for as they're not a lot, get the later 'blue' one. Or borrow one to test it if you can.

[drivebycar]

Did you notice if your coolant hoses were under alot of pressure? Sure sign of gasket failure.

Pretty sure they werent under alot of pressure, squeezed the rad hose to see if there was any oil in the expansion tank and didnt notice anything.

Me and a mate are going to have a look over it tonight and see if we can diagnose where its going wrong!

cheers for al your help