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                         Looking for some advice please. I bought a Corsa C with a 1.2 16v engine with 70,000 miles and FSH. 
Shortly after buying it, I discovered that the exhaust followers on cyl 3 and 4 had detatched from their proper position - i.e. the 'cup' was no longer located on the hydraulic lifter. The car was running rough with a lot of top-end noice. I took the cam out, inspected it (it's worn, but not excessively so) and refitted the followers. 
All was fine for a few hundred miles, then yesterday one of the followers on cylinder 1 islodged itself and the OBD flagged a fault code P0301 'misfire in cylinder 1'.  
Today I took the cam out again - and re-fitted the follower...... but what could be causing it? It's now happened on 3 different cylinders. 
The only other 'sympton' is on cold startup, the top end rattles like a bag of bolts for 3 or 4 seconds while the lifters fill with oil - but that's fairly normal, right? 
Here's a couple of pictures -  
1. with the cam still in situ : flic.kr/p/WUjePg 
2. with the cam removed : flic.kr/p/WUjeUB 
                            
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