Strange noise when accelerating

[AlanTR]

This concerns my stepdaughter's '04 Megane 1.5 dCi (86 bhp) which has done approx 52K miles. The car has a full Renault dealer service history. This car used to be mine (from new) 2 years ago and I drive an '08 1.5 dCi (106 bhp) model now.

When you accelerate hard, there is a hissing/whooshing sound ("sounds like air"). Once you reach your desired speed, the noise disappears and everything sounds normal. I test drove the car this afternoon and the performance seems to be ok and the exhaust is clean.

She's had the car to a local dealer who wants £60 just to investigate it. Anybody had this experience or got any ideas what it might be??? Any advice much appreciated.

[shawty500]

possibly air filter? take it out, give it a clean, maybe change it.

I get a hissing sound, more of a whistle, but thats definately the turbo (normal) but having had it yourself, and having another turbo diesel, that obviously isnt your concern

[davelowe]

I would check all the air hoses for splits and or loose connections. Check the intercooler hasn't split (has been known to happen on some diesels - but not all models). Make sure the turbo actuator moves freely by hand and springs back. I'm assuming that the noise only occurs when you are commanding acceleration by opening the throttle at low engine speeds and that the sound disappears when the revs increase (experiment if not known). If that is the case, then my car does the same; not entirely sure why, but it doesn't present as a problem.

[darkmast3r]

My 1.5 dci 53 plate does the same, seems as if there's not enough sound proofing there but the car drives fine