Hi there, thank you for answering. According to other users and drivers of Peugeot 307 my problem is related to the faulty exhaust manifold. I've heard that some people needed to replaced the manifold more than one time and that in some cases, the problem returned latter! Is there anything more I can do to solve the problem, like is the problem related to anything more or should I replace something more? Would replacing the manifold for other one compatible with the engine (like from other brand) solve the problem. Does someone been having the same problem over and over and solved it? Thank you very much in advance and best regards. Diogo M