Head gasket failure Insignia A Turbo

[ginger]

Hi everyone,

I wanted a little advise. I bought a petrol 2.0 Turbo Elite about 8 months ago at 79k. It was in great condition, or at least I thought.
I drove about 2k miles before the turbo packed up on the on ramp of the A3 coming off the M25. Luckily it was still under warranty from the garage I bought it from, so they replaced the turbo at no expense to myself & I have had no issues with it until I noticed a drop in coolant about 2 months ago. I checked for leaks & couldn't find any. Checked the oil but everything seemed fine, so I topped up the coolant & continued driving.
I then noticed a regular drop, say half a litre every month. I kept checking the oil & alarm bells rang when the oil level was increasing. I still couldn't see any signs of coolant in the oil, so continued to top it up & kept an eye on the temp while driving.
This weekend I did an 80 mile round trip & before leaving put in about half a litre of coolant, thinking that it was much lower than expected. Then on returning I had a coolant low warning & on parking up at home I found the expansion tank was almost empty.
I then checked the dipstick & the fill cap & found evidence of coolant in the oil.

I haven't driven it any further & an planning on getting it into the garage tomorrow.
My question is, seeing as it has never overheated what are the chances that the head is warped? Should it just be a gasket replacement & if so why would the gasket fail despite there being no overheating? Additionally could this be traced back to the turbo being replaced?

Sadly I'm not a stranger to heads going. Here is a list of previous cars I've owned that suffered to same fate:

Metro K series 1.1
Peugeot 306 1.9 Diesel
BMW Z4 3.0

Maybe it's me :/ I do tend to drive them pretty hard.

[Alex421]

When the head is off to replace gasket it should be checked and skimmed if needed.

[Dave1419]

Hello and welcome----------Dave

[ginger]

So the plot thickens.

I had the RAC come out & take a look. He did a CO2 test which was negative, suggesting that the gasket seal is fine.
I then took it to my local garage who have done a pressure test which suggests I'm losing no more than 0.1 of a bar? Seems any loss would be a negative?
They filled the coolant up & took it out for a 20 minute run & left it idling for an hour & experienced no coolant loss.
They have now added UV dye to the coolant, ran it & again can't see any evidence of the dye.
Whats more they claim there is no coolant in the oil, which I am dubious about as I definitely saw moisture & fudge under the fill cap.

It seems to be a mystery. All I know is a litre of coolant doesn't just vanish.

Any ideas?

[Thebat18]

I took my egr valve out and that pipe that sits next to it, and up to the intake.
And I discovered a lot of coolant.
Out came about a cup full of water.
I am almost certain that, that is not right.

- that could be the cause of my coolant leak.
You can see if you have the same leak.
It vaporizes up in the intake and get burnt.

[Alex421]

That's good news...
I'd be still worried to with the previous water loss.

[minisprint4230]

I had a Cavalier with head gasket issues, you could drive all day without overheating or using coolant, but when you went over 60mph car would overheat and loose coolant, ran it for 6 months till I changed it, the failure was between cylinder 3 and 4.

[lizzard-t]

I don't know if those engines have dry or wet liners but could be them

[Alex421]

Surely would have shown on the sniff test if gasket was gone.
Moisture can build up on oil caps an go like mayo if you do a lot of short journeys.
None of those explain the water loss though.

[ginger]

I took the Insignia to another garage last week. They suspect a cracked cylinder head, or the oil cooler. To determine either would mean a strip down & that would be £300 just to investigate the oil cooler. As you can expect I'm not over the moon. Cost to replace the cylinder head....£2000 or there about.
Another mechanic friend thinks it could be the EGR Cooler, which is apparently a common problem.

Looks like its the big scrap heap in the sky for this old girl. She's not worth the cost of the repairs, which is a shame as body wise she is in mint condition & the interior is just as tidy All in all this car has been more trouble than it's worth.

[BodgeItAndScarper]

If they want to play parts roulette, they haven't got a clue what's wrong.

I would give the coolant hoses a really close inspection, especially the ends. If you have a leak under pressure, if the coolant is hot it can instantly turn to steam when it escapes and is no longer pressurised. You tend to get some flaky deposits left behind, but not always.

[Drew]

If they want to play parts roulette, they haven't got a clue what's wrong.

I would give the coolant hoses a really close inspection, especially the ends. If you have a leak under pressure, if the coolant is hot it can instantly turn to steam when it escapes and is no longer pressurised. You tend to get some flaky deposits left behind, but not always.

As above check all the coolant system. It's common, with age, for the lower nearside radiator bracket to corrode, snap and cause a leak. It did on my 2012 Sri. Only noticed it on a dry day. I thought I had lost fluid a couple of times whilst towing but it was the snapped bracket.

[Alex421]

I took the Insignia to another garage last week. They suspect a cracked cylinder head, or the oil cooler. To determine either would mean a strip down & that would be £300 just to investigate the oil cooler. As you can expect I'm not over the moon. Cost to replace the cylinder head....£2000 or there about.
Another mechanic friend thinks it could be the EGR Cooler, which is apparently a common problem.

Looks like its the big scrap heap in the sky for this old girl. She's not worth the cost of the repairs, which is a shame as body wise she is in mint condition & the interior is just as tidy All in all this car has been more trouble than it's worth.

Has anyone done a pressure test on the cooling system surely would show cracks in cylinder head or cooler?