Car won’t boost more than 5 psi, boost leak?

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Shoppinit
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Re: Car won’t boost more than 5 psi, boost leak?

Post by Shoppinit » Wed Jun 13, 2018 11:37 am

The RS6 has its own collective noun for them. It's "an orphanage of bastard bolts".
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 -- XC90 (V8, natch)
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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Re: Car won’t boost more than 5 psi, boost leak?

Post by PipRS6 » Wed Jun 13, 2018 1:07 pm

Shoppinit wrote:
Wed Jun 13, 2018 11:37 am
The RS6 has its own collective noun for them. It's "an orphanage of bastard bolts".
:lol: :lol: :lol:

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Re: Car won’t boost more than 5 psi, boost leak?

Post by bam_bam » Wed Jun 13, 2018 7:56 pm

Shoppinit wrote:
Wed Jun 13, 2018 11:37 am
The RS6 has its own collective noun for them. It's "an orphanage of bastard bolts".
What's the collective noun for RS6s?

A money-pit of RS6s?
No matter where you go, there you are.

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Shoppinit
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Re: Car won’t boost more than 5 psi, boost leak?

Post by Shoppinit » Wed Jun 13, 2018 11:02 pm

A tribulation of RS6s.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 -- XC90 (V8, natch)
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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Re: Car won’t boost more than 5 psi, boost leak?

Post by simonpoulton » Thu Jun 14, 2018 8:00 am

Bankruptcy?
Current: RS6 C5 Avant, E60 5 Series, '78 Mini (Queued for restoration)
Past: R56 Mini Cooper S

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Re: Car won’t boost more than 5 psi, boost leak?

Post by Daveperc » Thu Jun 14, 2018 11:00 am

All much too miserable!! :bash:

My vote goes for a "Grin" of RS6's!!

Ive always argued that the measure of RS6 travel is not MPG, but GPM - "Grins per mile"!! :boots: :boots:

Enjoy your Beast!!

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Re: Car won’t boost more than 5 psi, boost leak?

Post by PipRS6 » Thu Jun 14, 2018 11:21 am

Daveperc wrote:
Thu Jun 14, 2018 11:00 am
All much too miserable!! :bash:

My vote goes for a "Grin" of RS6's!!

Ive always argued that the measure of RS6 travel is not MPG, but GPM - "Grins per mile"!! :boots: :boots:

Enjoy your Beast!!
Smiles per gallon always works. Lets be honest the last thing you buy an RS6 for is to be cheap.....

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Shoppinit
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Re: Car won’t boost more than 5 psi, boost leak?

Post by Shoppinit » Thu Jun 14, 2018 9:02 pm

Yeah. See it as a status symbol. Thanks for the wake up call, Dave. :thumbs:
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 -- XC90 (V8, natch)
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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8520
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Re: Car won’t boost more than 5 psi, boost leak?

Post by 8520 » Thu Sep 20, 2018 4:17 pm

Been driving the car a lot more so it’s time to address this more seriously.

Scanning the car while driving I noticed my maf readings are a bit different than each other but not by much. I presume they shouldn’t be exactly the same.

Only code I have is for a bad engine mount. I heard one guy saying that a bad engine mount code caused his car to do the same thing. Any merit to this statement?
03 RS6 sedan V8TT, 03 S6 Avant V8, 06 Touareg V8, 03 Silverado V8

All V8’s in my garage because America :mrgreen:

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Re: Car won’t boost more than 5 psi, boost leak?

Post by Shoppinit » Fri Sep 21, 2018 11:55 am

I have heard the engine mount theory before, long time ago. Theory is that the ECU limits power to prevent excessive movement of the engine. However, I seem to remember disproving it, but I don't remember how now.

You can get little plugs to fool the ecu that the mount is working. You could try this, I suppose, but don't get your hopes up too much.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 -- XC90 (V8, natch)
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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Re: Car won’t boost more than 5 psi, boost leak?

Post by R56WUF » Fri Sep 21, 2018 12:38 pm

Is it an engine out job to deal with the mounts correctly?
2004 C5 RS6 - Missano Red (the fastest colour...) - Departed
2004 C5 RS6 - Sprint Blue (the prettiest colour...)

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Re: Car won’t boost more than 5 psi, boost leak?

Post by 8520 » Tue Sep 25, 2018 7:37 pm

R56WUF wrote:Is it an engine out job to deal with the mounts correctly?
I wouldn’t think so. I would imagine you could lower the subframe while while keeping the engine raised to allow access.

Any more thoughts on the engine mount being my issue or what I should be looking for when logging?
03 RS6 sedan V8TT, 03 S6 Avant V8, 06 Touareg V8, 03 Silverado V8

All V8’s in my garage because America :mrgreen:

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Re: Car won’t boost more than 5 psi, boost leak?

Post by Jayjay101 » Tue Sep 25, 2018 8:20 pm

Daveperc wrote:All much too miserable!! :bash:

My vote goes for a "Grin" of RS6's!!

Ive always argued that the measure of RS6 travel is not MPG, but GPM - "Grins per mile"!! :boots: :boots:

Enjoy your Beast!!
Dave with the truth once again-there not cheap-there a pain in the arse but there sexy to look at and go like a bat out of hell...........bit like high class call girls


Sent from my iPhone using Tapatalk

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Re: Car won’t boost more than 5 psi, boost leak?

Post by GreggPDX » Tue Sep 25, 2018 8:37 pm

8520 wrote:
Tue Sep 25, 2018 7:37 pm
R56WUF wrote:Is it an engine out job to deal with the mounts correctly?
I wouldn’t think so. I would imagine you could lower the subframe while while keeping the engine raised to allow access.

Any more thoughts on the engine mount being my issue or what I should be looking for when logging?
The fact that the ECU is requesting boost would rule out the engine mount (IMHO). The ECU is asking for it, so assuming the N75 is working, then it sounds like something mechanical in the turbo "system". The fact that your don't see a large difference between MAF's should rule out a dead turbo or stuck wastegate. Maybe a failed diverter valve? If one is stuck open, I believe that would reduce boost.

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