Dropped a valve ?

[Skittles]

I’m guessing that making the extra oil changes helped my engine to get to 111k before self destructing.
My loan Berlingo has now done 35k (56000km)  - I’m wondering what they would say if their van suffers the same  problem at 60000km ?

Sorry to bring an old thread up, but got a Peugeot 308sw in that has the 1.5 bluehdi engine. Twin cam version late 2018.
90,000 miles on clock. 
Belt kit changed at 87,000 miles. Serviced every 10,000 miles or less. Looked after very well. Private hire vehicle. One careful lady driver. 
3 weeks after belt change, engine light came on. 2 faults stored, regarding air flow high, and low. (outside parameters) 
Initially suspected egr valve, after confirming belt timing was still 100%,and replaced with genuine part. The faults remained.
Not wanting to throw good money after bad, and conferring with other mechanics, recommended a dealer diagnostic. 
Dealers diagnosed air flow meter as a starting point, They duly changed it, and lightened my customers purse by just over £400.
2.5 miles later the light was back on. She returned to dealers, who frightened the s**t out of her by saying it needed to be put on a different diagnostic machine, and there were 17 steps to go through. Basically, they were going to throw parts at it, exactly what I was trying to avoid. Their estimate on cost was upwards of £5000 for a new engine. 
So despite the voices in my head screaming "don't touch that pile of French s**t!", I took it back on.
Here's a list of symptoms. 
Cold start rattle, like a vauxhall corsa. 
Poor turbo performance. Laggy and no top end. 
Pulsing through inlet system, like cam timing out or bent valve.
Emissions slightly higher, failed mot test. 

So, I reluctantly stripped the cam box off today. Didn't want to, but everything pointed to cam chain. After 2 hours at a snails pace, it was removed. Not really a bad job, but when you don't wanna...... 

EUREKA!!!!!! 

The cam chain tensioner is broken. No obvious major damage. Will need to do a leak down test for valve damage. The camshafts have pressed on lobes, so they are questionable. They may have spun if the valves hit the pistons. 
So it needs a minimum of a chain and tensioner kit. Maybe camshafts to be safe. Probably will be genuine parts. I haven't found any pattern ones available yet. 
It will live again! 

But here's the rub. The dealers know about this fault. There was a bulletin issued, and the service agent did mention a chain issue to my customer. It depends on the chain size, 7 or 8mm. The 7mm chain is the issue, and should be covered by peugeot. The thinnest chain links do measure up at 7mm,so this job may have been covered, even outside warranty limits. But my customer is rightly untrusting of the dealership now. They should have known this could have been the problem all along, and acted in good faith. Instead they've fleeced her of over £400.

I hope these symptoms might help others with the same issue. It's been a headscratcher. Not what you'd expect from a relatively young car. I'll post the final results once the job is finished.