Hi I have a Citroen c4 56 plate 77k miles on the clock. I had a blown head gasket as my oil was leaking into the coolant. Had this repaired at the garage and they also changed the cam belt. 2 days later, covering only 50 miles on short distances the car started cutting out when the engine got hot and was low revs (at traffic light for example). Took it back in and they said it was the crankshaft sensor which they replaced. Drove away and straight away another warning light STOP oil pressure too low, this goes away once revs are put on but immediately comes back after stopping. All this within one week and barely even drove after getting the head gasket replaced. It was sold with having a 12 month warranty but obviously only relating to the gasket. My question is do you think this is because of the repair, perhaps not done properly. It was supposed to have proper pressure tests but obviously have not seen these. Any help is much appreciated, many thanks.