Mazda Rotary Club

General => General Technical => Topic started by: cush on August 18, 2008, 06:06:28 PM

Title: whistleing sound
Post by: cush on August 18, 2008, 06:06:28 PM
hi i have the fd3s and i now have a loud whisteling sound when i hit 4500 revs just as the second turbo comes in does any one know what this could be cheers
Title: whistleing sound
Post by: RedRummy on August 18, 2008, 08:44:41 PM
boost leak?

whats the boost pattern like?
Title: whistleing sound
Post by: cush on August 18, 2008, 08:57:24 PM
i thought it might be a boost leak and i dont like putting my foot down when it does it so havent had chance to look at the boost pattern would it be ok for me to put my foot down to test it do you think ?
Title: whistleing sound
Post by: m1tch on August 18, 2008, 09:14:14 PM
Wastegate opening?
Title: whistleing sound
Post by: cush on August 18, 2008, 09:31:10 PM
no it is definatly like a leak as it never used to do it and i know it doesnt boost properly when i get to the second turbo in all gears
Title: whistleing sound
Post by: Locki on August 19, 2008, 04:05:27 PM
Hi mate, sounds like the above, could be a boost leak or even a faulty check valve (some of mine were knackered and made a funny noise) only other thing i can think of is the ACV. Get a m8 to rev the car while you\'re under the bonnet to see if you can pinpoint where it\'s coming from
Title: whistleing sound
Post by: RedRummy on August 20, 2008, 12:07:34 PM
if its at 4500rpm, when the secodn turbo comes in, then is it likely to be something to do with how the transition between first and second turbos works...

it is difficult to diagnose, you\'d need to speak to someone closely familiar with the turbo pack to find out the sequence of events that happens when boost pressure is passed from 1st to 2nd tubby.

probably some kind of internal valve not closing properly...  do you still get ANY boost above 4500rpm?
Title: whistleing sound
Post by: Bobbit on August 20, 2008, 12:39:24 PM
Check the y-pipe coupler, i\'ve had this 3 time and each time the coupler had either split of just come loose.The last time it happened i was having a play with a skyline r35 and he left me for dead, gutted!
Title: whistleing sound
Post by: RedRummy on August 20, 2008, 02:08:20 PM
Actually, I had to change my y-pipe coupler, and it was making a whooshing sound (not whistling though), so yeah, could be that - easy to fix too, so worth doing if its old and looking tired.

you might have the original coupler on there - the original one is black plastic (it joins the Y-pipe to the cross-over pipe)... aftermarket ones look like silicone tubing as on the intercooler piping.