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Discussion Starter · #1 ·
So, car is a 2014 with the CREC engine on about 54k, has an MRC stage 2 with crank pulley, running 470bhp.


Last week after my normal 30 mile drive to work I noticed a little vibration at idle, scanned with VCDS, showed no codes.


Took it out for a bit of a more spirited drive, logged a cyl 5 misfire, swapped plugs/coilpacks around, misfire stayed on cyl 5. Compression test came back at 150psi for cyl 4 & 6, cyl 5 only 75 psi.

Leakdown test shows valves are all sealing correctly, also with the charger off looking into the ports it all looks very clean. Air is escaping into the crankcase. So it's got to be either rings or a piston issue. Surprising considering its only done 54k miles.

Car is currently at my mechanics 3rd in the queue for a rebuild :(

Anyone else had similar issues? What were the causes?

Also while it's bits what else should I have done? I don't want to get it fixed and back on the road only for something else to go in a few weeks time.

Other than PCV, waterpump and thermostat is there anything else worth doing?
 

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Blimey mate not a good tale. Was the engine consuming oil or water before this happened?? Or overheating?? Was the oil clean?? Seems very strange as you say at such a low mileage. Please keep us informed. Ps auto or manual?
 

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Discussion Starter · #3 ·
Oil was changed in May last year, then again just after it was remapped in October, no over heating issues or noticeable drop in performance either.

I'd say it used about a litre in 4000 miles, I do drive it pretty hard but it's always allowed to warm/cool properly.

Not sure what the oil in it now looks like, probably full of bits of piston with my luck lol

It's DSG.
 

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To consume a litre in 4k miles of hard driving I would say is good and indicates a healthy engine in my opinion. Recently I drove my old S4 V8 6k kms from Italy to the UK and back and she used about one litre of oil which I consider fantastic. I drove through snow and rain almost all the way too!!! Seems very strange that then your car kind of gave up????
 

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Discussion Starter · #12 ·
I got them direct from Redstar in Russia, Brotek in Scotland also sell them but didn't have any in stock although he did say he was ordering some. Heat exchanger was from him and arrived quickly with no issues.

Engine is out, filled cyl 5 and 6 with paraffin, 5 leaked out alot quicker than 6 so it's definitely piston/rings. Cylinder wall looks OK so hopefully just rings!

I've told him to check the chains and do the tensioners while it's out, should be good for another 55k when it's done :rolleyes:

Pistons should be coming out on Tues.
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Discussion Starter · #15 ·
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All pistons are now out, injectors all tested.

All of the pistons seem to have quite a bit of burning/blowby, I'm starting to think that maybe this is down to poor servicing before I got the car.

Any opinions?
 

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Hi mate what was the service history like on you car before you purchased it.
 

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Discussion Starter · #17 ·
It had done 43k when I got it and had 3 services, everything seemed fine and I had it serviced as soon as I bought it.

I'm wondering if maybe they let the oil get too low between services, guess I'll never know though!
 

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That is a bit worrying as the CREC engine was supposed to be much improved over the earlier gen which was also reliable strong motor.

The below page was taken from the CREC PDF and it has revised pistons and rings! Be curious to get to the bottom of why yours gave up!?

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Discussion Starter · #19 ·
Been struggling to get pistons for it, ordered through TPS but they couldn't give an ETA, very nearly bit the bullet this morning and ordered come custom JE ones however one last phonecall to TPS and they reckon they'll be here by the end of next week. The JE ones had a 10 week lead time so I'm glad the OE ones are going to be quicker.

The original ones were superceded in 2018 so will be interesting to compare with the old ones to see if there are any differences or whether it was just a change in supplier. From what I can see they're still made by mahle but will confirm when they arrive.

I'll have to do some logs when it's up and running.
 

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Discussion Starter · #20 ·
Pistons finally arrived and rebuild is in progress at last!

After further investigation piston number 5 has a little bit more damage than we initially realised, luckily it didn't give way while it was running!
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