Head gasket question - White foamy froth

[FiatPuntoMad]

First of all ill apologise, as this isn't relevant to punto's or even fiat. But thought it would be an appropriate place to post as i always post in the section, and i know punto's suffer from HG failure and have a punto myself.

A friends mum has a mk6 1.25 fiesta, few months back suffered from over heating (A LOT of it) found to be crack in coolant system, now fixed. Few weeks ago was only running on 3 cylinders, diagnosed on computer and found to be coil pack. Got this changed and now this weekend its running rough again, intermittently struggling to start and running on 3 cylinders again with engine management light on. She asked me to take a look for her.

First looked for HG issues as it has suffered badly from over heating, oil was fine and no 'mayo', coolant level fine, only thing i noticed was a lot of white frothy foam in coolant reservoir. Is this a sign of HG ? everything else seems OK.

Heaters also blowing cold, but this is a common problem with a stupid switch/sensor thing that ford stupidly put in for no apparent reason. Now I'm thinking this could also be a HG issue?

Again i apologise but i told her id ask around on here for her help would be much appreciated :worship:

 

[FiatPuntoMad]

Also didn't mention temp gauge always shows half way but engine fan is pretty much always on. Soon as the car comes to a stop the fan kicks in. And is constantly on at speeds of around 20mph and under.

In my punto it very rarely comes on at all, only in crawling traffic after 5 or 10 mins, and even then its only briefly.

 

[Dcthebear]

Fiesta fans kick in really low for some reason, probably to help push the car along. May be the engine temp sensor playing up. As for the froth in the coolant, there could be a wide range of reasons from exhaust gases seeping through the HG to someone accidently (I hope) putting screenwash in the coolant! For the cost of it, I'd flush the coolant system and put some nice new stuff in to see if it helps.

 

[FiatPuntoMad]

Okay thanks we'll flush it and see if it gets any better

Was just a little concerned the HG may be damaged coz of all the previous overheating.

Again apoligies for it not being related

 

[s and b]

if it was low on coolant it might go frothy man
due to being whipped into a froth
suggest if water up to level investigate why no heat
it might just have had a miracle cure added to the system thats gone t*ts rather than had the original problem fixed

seen dis wit me own eyes afore now

 

[FiatPuntoMad]

In a fiesta there is some kind of valve/swtich thing near the heater matrix that is a really common problem on fiesta, will investigate this. Coolant level wasn't low, but we'll see how it goes after a coolant change

 

[Ziggy122]

In a fiesta there is some kind of valve/swtich thing near the heater matrix that is a really common problem on fiesta, will investigate this. Coolant level wasn't low, but we'll see how it goes after a coolant change

If the valve for the heater matrix is sticking Shut and not opening

It can give the signs of a HG
Ie
Overheating due to airlocked system
No hot air in cabin


Foaming is probably some twonk adding something too coolant

Ziggy

 

[PuntoHowTo]

Your theory about the matrix isolator valve is easy to test (seriously do for still fit these?), warm up engine and feel the top radiator hose, if it's nice and warm then the valve is probably stuck, double check be feeling the hoses going to the valve. It is a common problem they do stick closed but the heater matrix doesn't cool the engine so it shouldnt overheat the car!

The key clue is the crack in the cooling system, did it crack because of age/wear or did it crack because of pressure? My money is on the latter.

The previous episode of over heating could have knackered the thermostat (and also the matrix valve) which could account for your current over heating problem however I'm going to put my neck out and suggest it could be a blown head gasket. Excess pressure put into the system by a blown head gasket has to escape some how and the cap on the coolant bottle is designed to release excess pressure. Any gasses bubbling throught the system are going to find their way to the tank and bubbling mixed with exhaust gasses and anything else pushed into the system will create foam. It have been gone a while and the crack was the first sign of the excess pressure, you need to change or remove temporarily the thermostat and warm the car up to see how quickly it heats up and if you see bubbles forming in the coolant tank, of course the easiest way to confirm is to get a compression test or coolant sniff test done

 

[FiatPuntoMad]

Thanks

Yeah another family member told her many months ago he thought her HG was on its way out.

Its booked in for a sniff test i believe after getting a second opinion on it.

Everyone is confused as its showing certain symptoms but not others expected to come with it. But the test should show up any problems. I think that chances are, the HG is gone, theres been something not quite right for quite a while now!

Starting to worry bout my own HG now temp dial seems to drop when setting off and oil level appears to be rising, although theres no coolant loss. Also smells very strongly of petrol sometimes so I'm wondering if petrol is getting into the oil.