No boost, possible failure of turbos.

2.7 V6 30v biturbo - 251bhp
2.7 V6 30v biturbo - 261bhp
DavidT
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RE: Re: RE: No boost, possible failure of turbos.

Post by DavidT » Fri Aug 03, 2007 10:05 am

The air is not sucked in is it, I thought atmospheric pressure pushed it into the vacuum :)

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derdle
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RE: Re: RE: No boost, possible failure of turbos.

Post by derdle » Fri Aug 03, 2007 10:17 am

The air is not sucked in is it, I thought atmospheric pressure pushed it into the vacuum
Technically correct...but easier to explain using the word "suck".
(Most blokes understand the word "suck", try to explain a BJ any other way? (but that's way way off topic)).
RS4 in the only colour to have - Misano Red | MRC Remap | RS6+ brakes | H&R and Custom Performance Parts suspension |
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RE: Re: RE: No boost, possible failure of turbos.

Post by DavidT » Fri Aug 03, 2007 10:26 am

LOL, yes.

Anyways, how is this fella getting on with with car I wonder ?

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RE: Re: RE: No boost, possible failure of turbos.

Post by C-24 » Fri Aug 03, 2007 3:25 pm

Try to unplug your MAF sensor, that was my problem (the car had no boost above 3k rpm)

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S4 avant imola yellow
Sportec remap 320hp / 500nm
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derdle
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RE: Re: RE: No boost, possible failure of turbos.

Post by derdle » Fri Aug 03, 2007 3:28 pm

Try to unplug your MAF sensor, that was my problem (the car had no boost above 3k rpm)
...and then plug it back in again?
RS4 in the only colour to have - Misano Red | MRC Remap | RS6+ brakes | H&R and Custom Performance Parts suspension |
Huge Grin :biggrin3: If you dont "do it now" you never will.

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ZeroK66
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Re: RE: No boost, possible failure of turbos.

Post by ZeroK66 » Fri Aug 03, 2007 3:29 pm

UKS4APR1 wrote:
confusionhunter wrote:
Nah mate, thats still no boost, you get a reading of 0 in NA cars when they at Wide open throttle.... means its at atmospheric pressure.
N/A engine would not be running at 0 ! how would the air be getting to the cylinders? It takes Boost to get to 0. You either suck it in (vacuum) or force it in (boost) it can't just go in on it's own.
Drive your own car from 800rpm put your foot flat and before your turbos even spool your boost gauge WILL show 0 - as stated here - the internals of the engine are at atmospheric pressure. Air in an NA car gets pulled in, when there is no restricter at the inlet - IE: Throttle fully open - you will get NO vacuum.

Anyways, I did boost logs and even though I had one working turbo and one seized turbo I got NO boost as the engine could not build up enough RPM/gas movement to spool the working turbo to provide boost. My boost logs showed a constant atmospheric pressure.

******************

Anyway, back to the subject at hand...


if the noise you describe is like a grinding noise - turbo is dead. If the noise you describe is like a wooooooooooooo (ghost) sort of noise same again - turbo dead.

Lets hope it is neither and it is simply a split hose/something popped off.

Cheers,
Facelift Imola S4 | Cust K04's, Tubular Manifolds, 3" DPs->2.75" Catback | FMIC | PSS9 Coilovers + ARB's | Brembo 8-Pots | SS + DTS | 5??HP/475lbs/ft | 3.06S FATS on S4 Box

Sold: A4 (B5) 2.8 Quattro | Ivory Pearl
Melted: Corrado - IHI 1.8t: 343BHP

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Re: RE: Re: RE: No boost, possible failure of turbos.

Post by C-24 » Fri Aug 03, 2007 3:41 pm

derdle wrote:
Try to unplug your MAF sensor, that was my problem (the car had no boost above 3k rpm)
...and then plug it back in again?
No. My MAF is always unplugged, because when plugged in it set the car to "limp mode" and it's has like 100hp less.
You have to buy a new MAF to resolve the problem, or you can drive your car without the MAF (that's what I'm doing).
S4 avant imola yellow
Sportec remap 320hp / 500nm
Brembo GT-brakes
RS4 suspensions

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ZeroK66
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RE: Re: RE: Re: RE: No boost, possible failure of turbos.

Post by ZeroK66 » Fri Aug 03, 2007 4:48 pm

You could potentially damage your cats running without your MAF I would have thought? The car runs 25% richer over the standard map - so you are dumping fuel into the system like there is no tomorrow... chances are 10 tanks of fuel you would have paid for a new maf in economy!
Facelift Imola S4 | Cust K04's, Tubular Manifolds, 3" DPs->2.75" Catback | FMIC | PSS9 Coilovers + ARB's | Brembo 8-Pots | SS + DTS | 5??HP/475lbs/ft | 3.06S FATS on S4 Box

Sold: A4 (B5) 2.8 Quattro | Ivory Pearl
Melted: Corrado - IHI 1.8t: 343BHP

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