boost leak test

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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Mumbbles
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boost leak test

Post by Mumbbles » Thu Mar 07, 2019 10:16 am

Hi all
ive brought a boost leak set its coming at the weekend but just wanted to check if this will do all the vacuum lines as well.
the kit is https://www.ebay.co.uk/itm/Sealey-Turbo ... 2749.l2649

i have had no boost from the car for a year now replaced all boost sensors all boost lines/ turbos/ maf. engine out three times and can't seem to find the culprit.
the car will not rev over 2500 get and big dop in power its like the car is braking all the time but driving normally without boost its ok.
now im getting oil leaking from back of engine both sides looked at the breather hoses and got some gunky oil in them like its been mixed with water?
i thnik there is a blockage somewhere in the breather system but can't find it.
so my question is will the leak test do the vacum lines as well.

thanks

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Shoppinit
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Re: boost leak test

Post by Shoppinit » Thu Mar 07, 2019 10:52 am

Don't think that kit will help you with vac lines. If you've got a compressor can just set it to 0.5bar and use a pistol to check the vac pipes.

You're going to need do do some diagnostics with the Vagcom.

What fault codes are you getting?

What are your MAF readings?

If the car won't rev over 2500 that sounds like a fuel supply issue. Could be a dodgy pump or could be a blocked carbon canister that isn't allowing the fuel tank to breathe. Will it run over 2500 if you remove the filler cap? Have you checked the fuel pressure?

The blocked carbon canister could be a symptom or cause of the gunged up PCV pipes, possibly. I don't know a lot about the PCV system on the RS6. Might be worth replacing all the bits.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"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."

Mumbbles
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Re: boost leak test

Post by Mumbbles » Thu Mar 07, 2019 11:02 am

done all the fuel lines and new pump in tank and bosch 044 new pump outside the tank but still no difference
maf sensor goes out of spec g70 all the time replaced both new and changed connectors. no change
checked both IC in bath blocked both ends no leaks!
i will be doing the gearbox this weekend with new oil and filter thinking it might be this.
the carbon canister is behind the front driver wheel? then leads to the tank correct,this i haven't checked yet.
have got compressor so where be the best place to plug it into the pcv system

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Shoppinit
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Re: boost leak test

Post by Shoppinit » Thu Mar 07, 2019 11:07 am

I don't think you'll get any meaningful information from using a compressor on the PCV system as a whole. It'll just blow into the crank case. But like I said, I'm no expert on the PCV bit so happy to be corrected.

From memory, the carbon canister is behind the arch lining where you said. The N80 is there, too. You could probably replace that to eliminate, too. All the vac lines need checking. There's one going to the N80, too.

You need to log the MAF values when you are idling and driving. Especially interesting to see what they do when you are requesting boost.

If the gearbox was asking for reduced torque, it wouldn't be as violent as you describe. Plus, you can check for that with the Vagcom. Also, I suspect it would throw a fault code. There are some basics you can check with the Vagcom on the gearbox like making sure it's in the gear it thinks it is, etc. I think it would give all sorts of obvious signals if the issue was coming from the gearbox.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"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."

Mumbbles
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Re: boost leak test

Post by Mumbbles » Thu Mar 07, 2019 11:25 am

Hi Shop
i had a remap done two years ago and seem to have problems after the remap with electrics failing like ABS and Headlight range not working but only left side.
but had the car of the road for about 5 months and ECU unplugged. would this reset the ECU to standard or would it retain memory of the map.
just thinking this might be bad remap or ecu.

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Shoppinit
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Re: boost leak test

Post by Shoppinit » Thu Mar 07, 2019 11:51 am

Leaving it unplugged won't reset it. You would have to flash it back to standard or get it mapped properly.

The original binaries are floating around somewhere, on nefarious motors, I believe. Or you could ask someone like Viper to send you a good ladymap on one of his OBD2 programmers. Assuming he's still doing them.

/Rule 48 observed
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"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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Ben_r1
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Re: boost leak test

Post by Ben_r1 » Thu Mar 07, 2019 12:25 pm

With regards to leaking vac pipes I was taught a very food trick a few years back that’s helped me many a time.

Have the car idling and spray vac pipe areas in the engine bay with brake cleaner, anywhere there’s a leak present you should notice the pick up in RPM briefly. And if nothing else you end up with a clean engine lol.

Hope this helps.

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Shoppinit
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Re: boost leak test

Post by Shoppinit » Thu Mar 07, 2019 12:29 pm

^That's a good tip. Audi also sell an ignition inhibitor spay which does the same thing, but the revs drop.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"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."

Mumbbles
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Re: boost leak test

Post by Mumbbles » Thu Mar 07, 2019 12:37 pm

if i blow out the pcv lines will this do any damage just in case they are blocked with grungy oil.will it just blow back into the block, would it be better to take of the pcv line then blow them out.

Mumbbles
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Re: boost leak test

Post by Mumbbles » Mon Mar 11, 2019 11:13 am

Hi all
done leak test and a hissing noise coming from the left hand turbo can't seem to find out where its coming from as i put 10 psi down the inlet and when i put 20psi the other plug pops out which is good but still can't find hissing noise. any suggestion.

Mumbbles
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Re: boost leak test

Post by Mumbbles » Mon Mar 11, 2019 11:34 am

also i have a leak in the right hand back of the engine only when i rev the engine past 2000 rpm changed all the valve covers and chain adjusters.
the only thing i can think off is the camshaft ends, now is number four the only seal i need to get or is there o-rings i need as well
https://audi.7zap.com/en/rdw/audi+rs6+r ... -103040/#4

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Nobby
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Re: boost leak test

Post by Nobby » Tue Apr 09, 2019 2:19 pm

There aren't 'O' rings on part number 4 as far as I remember. They just push in.
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