Turbocharger Problem? Knowledge Needed.

[Tiger_kpt]

Right... literally less than 24-hours ago I got my car back from WGT\'s after over £3000 on parts and labour.

See the following link for full spec -
http://www.mazdarotaryclub.com/forum...ad.php?t=37511


Done a fair few miles in it since, all seemed fine. Until we stopped for some food and drink and left the car for 30-minutes or so.

Got back in and started her up.

Immediately a weird noise began. Best way to describe it is as a low pitched humming or farting noise! Imao. I know this about it: -

a) It is coming from around the area where the turbochargers are.

b) It only occurs at idle up to (and I mean on the dot) 2500rpm. At or over 2500rpm the noise disappears and the car is fine again. Below this the noise comes back at 2500rpm on the dot and below again.

It may just be me but she seems a little more juddery on the transmission also (could just be me though). Could this be a mount of some kind?

I\'m just wondering if any of you guys know of similar symptoms and could give advise. I\'m thinking it is turbocharger or exhaust side of engine related.

A few things that bothered me when the car came from Pip\'s, which may be or may not be anything. But I had the Greddy dump valve fitted on the Greddy elbow on a flange. Pip left the two standard dump valves on. So they are still at this side of the engine.

Also... cat was removed and Greddy pullies fitted. But instead of removing the airpump, he used the pullies with a longer belt and left the airpump active in the absence of the cat. I know that people complain about a "moo-ing" sound from the airpump coming from aftermarket filters. But this sound isn\'t that. It isn\'t coming from filters, coming from turbo area of engine bay. And occurs between idle (750rpm and 2500rpm), so this tells me it shouldn\'t be that. Also... as a test removed the airpump pipe from the airbox, sound still occurs.

So... any ideas guys? Am at my witts end after spending so much money on her and having less than a days pleasure out of her! Lol.

Cheers.

[shaunwil]

Best bet is to talk to pip.

Sounds like its the airpump that is causing the issue. If the cat has been removed it could be that the airpump is blowing air out under the car making the  noise.

Don\'t get too stressed, doesn\'t sound too serious !

Shaun

[gsb876]

Get on the buzzer to Pip and see what he thinks,

If you ever come out of a tuners garage not 100% happy state it there and then to their face only way you will get answers, Pip charges a fair whack and should provide top service for this price :2eek

I used to go to Pip all the time but the bill seemed to increase all the time for no reason and the last job he/they did was not very good left wires hanging out the bottom of the dash and car developed a earthing problem straight out of there too and charged stupid money for a average job :2Confused

Hence will be going elsewhere when the new RX arrives.

[Tiger_kpt]

Yeah. Like I say the car was fine driving home from Pip\'s yesterday and driving out today. Just driving back today that this problem developed.

Although, when on the dyno at Pips. There was a point towards the end that the car began burning oil (emitting a heavy blue-ish smoke) at idle. Which when revved and let to idle again, got rid of the problem.

Pip advised that the car may be in need of some attention to the turbochargers at some point in the near future. Possibly a turbocharger replacement or rebuild.

This happened again yesterday, but again, no issues and cleared up immediately. And again today, after I started the car up (as this new troublesome noise appeared). But the smoke cleared up and the noise remained.

I\'m going to let the engine cool down and try again, see if that makes a difference.

And will of course ring Pip tomorrow.

I know you guys said it could be airpump... but why over 2500rpm (when the first turbocharger engages) would the sound disappear completely?

I\'m under the impression that the first turbo kicks in at 2500rpm and the second at 4500rpm? But at idle... are the turbochargers spooling up or are they stationary?
I\'m thinking that when they are inactive and the exhaust gas is handled/circulated in a different manner... there\'s something wrong with that path of emission (when it is bypassed from the turbochargers - maybe blown gasket? Maybe i\'ve got my understanding of how the gas is handled with regards to the exhaust system there???

[shaunwil]

The airpump only works at low rpm.

Shaun

[interloper393]

cn i ask what the hell cost 3k if it wasnt a rebuild lol.. thats serious money bud..

[Tiger_kpt]

Oh... no. Only spent £1400 with Pip. That included de-cat Pipe. Greddy second hand stock mount intercooler. Re-map. And fitting of all of my other performance parts. Rest was on buying the many parts I didn\'t get from him.

[Tiger_kpt]

What RPM does the airpump work from and to? Anyone know this for sure? I realise that the airpump pulley spins all the time. But it\'s clutched right?

[interloper393]

unplug the wire connector for the airpump and see it the problems still there bud.. if it stops, then remove that badboy and get a smaller belt

[Tiger_kpt]

OK. Sounds like a plan mate. Any chance of a pic posted up which shows where I can find the airpump connector please?

[interloper393]

on the airpump bud, not sure where it is tho lol.. at the top/back i tink..

[Tiger_kpt]

OK. Will take a look tomorrow and try unplugging it. It is rather a loud aggressive noise though. Sounds like air escaping under pressure in time with the rotors revolving. Not metallic or clunky though if you get me and definitely from the turbocharger area of the bay.

[Tiger_kpt]

Seems alot hotter under in the engine bay also, that could be worth noting.

[gmogle]

My airpump went faulty in the end and barks....just disconnected it as I dont have a cat and all was fine. Give it a try matey.

[Tiger_kpt]

Well... sending a big thanks out to you guys yet again! Went to my car this morning, unplugged the airpump and no more drowing dog noises! Sweet as a nut. Thanks all. Worrying over and can now enjoy for the time being.