I know this is a dead thread but maybe a new posts will help it out. On my M342a2 I got my truck running strong yesterday, but my whistler doesn't whistle at all. I am 100% sure that it is in fact a c turbo after measurements and pictures. So does anyone know why this whistler wouldn't want to whistle? After running it and building oil pressure I didn't lose any pressure or burn any oil, that a faulty turbo would do. Also, the engine purred like a cat. Sounded normal all except that turbo not whistling.