Technical Weird temperature problem.

[canonlover]

Hello everyone!

I have this problem with my '00 Punto 1.2 8v MK2.
The engine temperature is behaving weirdly... When I keep my revs under about 1800, the engine doesn't cool or heat properly. So my temp gauge will start rising over half and the fan will start blaring. It will keep doing this, especially at idle. As soon as I start moving (or revving), the temperature goes back to half gauge and the fan goes off. If i keep the car at idle, the temperature will keep going up, and reach redline too if i don't start revving/moving. But if i open the bonnet, I can touch the engine block and the cooling tubes, and they feel normally warm, certainly not 130 degrees in there. The radiator feels a normal temperature too.
I also get no hot air from the vents... Which is a problem as winter's coming.

So.... I don't know what it might be. Thermostat is working, i changed that. Water pump i changed 6 months ago. Cooling fluid is the correct level.

I have read a similar thread I saw from searching in here... in there they suggest it might be the head gasket. Do you think it applies to me also? I have checked the oil level today and there's no "mayo" or anything abnormal in the oil i checked, just plain oil. Should I do more tests for this?

Thanks to anyone who can help or give me an opinion! James

 

[Ziggy122]

Hello everyone!

I have this problem with my '00 Punto 1.2 8v MK2.
The engine temperature is behaving weirdly... When I keep my revs under about 1800, the engine doesn't cool or heat properly. So my temp gauge will start rising over half and the fan will start blaring. It will keep doing this, especially at idle. As soon as I start moving (or revving), the temperature goes back to half gauge and the fan goes off. If i keep the car at idle, the temperature will keep going up, and reach redline too if i don't start revving/moving. But if i open the bonnet, I can touch the engine block and the cooling tubes, and they feel normally warm, certainly not 130 degrees in there. The radiator feels a normal temperature too.
I also get no hot air from the vents... Which is a problem as winter's coming.

So.... I don't know what it might be. Thermostat is working, i changed that. Water pump i changed 6 months ago. Cooling fluid is the correct level.

I have read a similar thread I saw from searching in here... in there they suggest it might be the head gasket. Do you think it applies to me also? I have checked the oil level today and there's no "mayo" or anything abnormal in the oil i checked, just plain oil. Should I do more tests for this?

Thanks to anyone who can help or give me an opinion! James

When your Idle - Your Start to overheat?
But when u drive you cool down

sounds possibly like there is air in the cooling system, See the Guides section on how to bleed a cooling system, and see if that help

Ziggy

 

[canonlover]

When your Idle - Your Start to overheat?
But when u drive you cool down

sounds possibly like there is air in the cooling system, See the Guides section on how to bleed a cooling system, and see if that help

Ziggy

Hey, thank you Ziggy for your reply!

Yes, that's about it. But the weird thing is that the overheating is sudden as well as the cooling down. It can get very high, very soon, and then go back down again, I thought it was kind of impossible that the whole of the water could heat up and cool down so soon. Another weird thing: The car can be very close to redline, then i switch it off and back on again, and the temperature gauge is now barely above middle...

I could also try bleeding the system, and see if that helps... But could this air have come in from nowhere? It started having this problem on a long term trip.

Thanks!

 

[Ziggy122]

Air Heats Up Alot quicker then water does, And if the air is sitting around the Water Temperature sensor - You get a spike in temp
You switch off and the Air cools quickly down

You Could have developed a leak, it can happen any time
Check the engine bay area for signs of leaks

Ziggy

 

[canonlover]

Air Heats Up Alot quicker then water does, And if the air is sitting around the Water Temperature sensor - You get a spike in temp
You switch off and the Air cools quickly down

You Could have developed a leak, it can happen any time
Check the engine bay area for signs of leaks

Ziggy

You're right, I didn't think about that!
In my engine bay area, I have a tiny, tiny oil leak from the cylinder head (not from the valve cover, I've already redone that seal). It's so tiny that I haven't needed to refill the oil more than you normally need to, but it's constant (if i clean it up and then run the engine for a while it will reappear).

Where you talking about water leaks? I did check and I don't have any, only that small oil leak.
Thanks!!

 

[Ziggy122]

You're right, I didn't think about that!
In my engine bay area, I have a tiny, tiny oil leak from the cylinder head (not from the valve cover, I've already redone that seal). It's so tiny that I haven't needed to refill the oil more than you normally need to, but it's constant (if i clean it up and then run the engine for a while it will reappear).
Where you talking about water leaks? I did check and I don't have any, only that small oil leak.
Thanks!!

Yea i'm talking about water/antifreeze leak mate

Sometimes air can get in where water can't get out, I'd Try bleeding the system first

And By Cylinder Head do you mean the Rocker cover? If So they are prone to leak and tbh not to worry to much about just check the oil regularly, and Air can escape easily in the oil system, it gets to the top of the rocker cover - goes via the Breather tube into the air intake and is process through the engine and out the exhaust nothing to worry about there



Ziggy

 

[canonlover]

Yea i'm talking about water/antifreeze leak mate

Sometimes air can get in where water can't get out, I'd Try bleeding the system first

And By Cylinder Head do you mean the Rocker cover? If So they are prone to leak and tbh not to worry to much about just check the oil regularly, and Air can escape easily in the oil system, it gets to the top of the rocker cover - goes via the Breather tube into the air intake and is process through the engine and out the exhaust nothing to worry about there



Ziggy

Uhmmmm... I'm growing unfamiliar with engine terminology since I don't live in Britain anymore I re did the sealing for the Cam Cover. What is leaking now is the seal under the cam cover.
I'll try bleeding the system... And giving a good look at the whole water system.... Thank you Ziggy for your help And the guides on this site are so useful, I already fixed my juddering wipers by using the guide! I'll use the guide for bleeding the water system.

 

[DaveMcT]

Rocker cover is the traditional name. Cam cover is a better name.

Check out the coolant bleeding guide. Bubbles in the cylinder head cooling passages can easily lead to a blown head gasket.

 

[red]

Not really a traditional name, more of a misnomer. A rocker cover would cover rockers. Rockers were fitted to engines where the camshaft was low down and worked the valves via vertical pushrods that operated rockers. The rockers then operated the valves. Such arrangements were called OHV (overhead valve) to distinguish from the more modern OHC (overhead camshaft) though of course valves are generally over the head (I'll leave side valve engines out of this). Overhead camshafts were at one time confined to performance engines but are now almost universal. Puntos engines therefore have camshaft covers and not rocker covers.

BTW, if there's a leak from the joint that is about 100mm down from the camshaft cover, that's between the head and the cylinder block and the home of the infamous head gasket.

red

 

[DaveMcT]

Rockers were also used on some OHC engines in particular the Honda bikes with single camshaft and angled valves. But point taken.

The old BL A and B Series engines had a flat top cyl head with valves springs and rockers sitting above the lump. The pressed steel cover was like an upside-down bath that sat over and around the valve gear. The gasket was made of rubberised cork and a major pain in the wotsits to keep aligned (even with Hylomar) while the cover was screwed down. I once tried a soft rubber gasket and that was even worse.

 

[red]

Happy memories of halcyon days... Whitworth and AF spanners... regular decokes... jumpers for goal posts...

Nostalgia ain't what it used to be.

Probably getting off-topic now.

 

[bonezee]

Just develped a similar problem and my punto is also misfiring slightly!.So i'm having a sniffer test done on saturday to find out for sure?.But to be honest i'm accepting that it probably is the head gasket!

 

[DaveMcT]

Bubbles blowing over the vent pipe into the top of the coolant tank are a sign - and of course dropping coolant level with no visible leak.

 

[canonlover]

BTW, if there's a leak from the joint that is about 100mm down from the camshaft cover, that's between the head and the cylinder block and the home of the infamous head gasket.

red

Yes Red, I'm leaking from there, I'm nearly sure it's the same place where the head gasket goes. As I said, it's a very, very small leak, it doesn't even drip when you park the car and leave it. Thanks for the nice story you told about the valves and rockers BTW

By the way people.... I looked at the guide for the bleeding and ok, it's for a Punto mk1 and i have an mk2, but should be the same right? I found the first screw on the radiator (pretty impossible to miss) but i can't find the second rear one... Should I take the air filter off to get a better look? Or do you think it's just a problem of me not knowing where to look? It just seems that I have a lot more cables running everywhere than in the guide's pictures.

 

[canonlover]

OOOK people!!!!!!!!

I followed the bleeding guide..... strangely NO fluid would come out of the back screw, but much of it did come out of the radiator screw as i topped it up, along WITH BUBBLES. Hooray they're gone! And the car is absolutely rock stable after that, won't budge from the middle mark, fan is always off.

Thanks to Ziggy for suggesting the bleeding!!!! ^_^ Hooray for Punto's!!!! Hooray for FiatForum.com!

 

[Jackniksmith]

Hi,
just been reading your thread and had a similar problem, my car overheated when on idle. I opened the bonnet to find the rad fan had sheared off the motor whilst driving not sure if this is your problem. I no this may have been the first thing u could have checked but just thought i would let you no

 

[canonlover]

Hi,
just been reading your thread and had a similar problem, my car overheated when on idle. I opened the bonnet to find the rad fan had sheared off the motor whilst driving not sure if this is your problem. I no this may have been the first thing u could have checked but just thought i would let you no

Ahahaha well wow no my fan was fine, it was spinning at top speed all the time... wwwwwrrrrrrrrrrrrrrrrrrrr! I solved it now

 

[bonezee]

Unfortunately my problem was more serious!.It was HG but luckily a neighbor used to be a Fiat tech and he had a look, Fiorst thing he did was a sniff test which came up positive so he took it away and stripped it.The gasket had gone before so it couldn't be skimmed but luckily it didn't need it.One of the spark plugs had cracked so it was firing all over the place,so a new set all round.He took the car late friday and got it back Sat lunchtime:slayer:and i cant believe the difference,it's like driving a new car 58-59MPG:slayer:.
But my word is a warning:devil:like you i thought it was just an air lock then 5 weeks later it became a HG. I wish i had listened to whitesei when he told me to ask myself -"why is there an airlock?" But thanks to my neighbor job done very cheaply and i'm so grateful to himotherwise i was looking at about£350-400 to get it repaired.
So if i was you i would get it checked if you have not already done so.