Hi everyone, excellent site & have picked up some useful tips thanks. I have a 307 sw 02 plate HDi 90 (I think!) it's not the 110 anyway. The car has been vibrating and has a very loud idling noise which isn't so apparent when you are driving it, took it to peugeot dealer twice & they replaced the pre tensioners, wasn't that. Then they wanted to order some huge part - I can't remember what it was but cost about £400. Not overly impressed, we took it to an independant who said he thought it was the air compressor unit. Could this cause the noise I've mentioned? I'm new at this and am no mechanic but am getting tired of being given conflicting opinions, just want to get the damn car sorted!! Any help muchly appreciated, thanks.