Low boost

[prj]

Sorry to hear its still causing you a paint in the butt Shaun.
Just to clarify me and TimE-J looked at the measuring block in Vagcom for the MAP sensor and it was totally static when we revved the engine which didn't seem right.

There is no measuring block in vag com for the MAP sensor, there is only atmo pressure, which is why it didn't change.

[Vorsprung durch Technik]

ive had a few good results tonight changed the N75 last night, took the car to the farm tonight for someone look at the air con, found a loose pipe so hopefully tighten that and i'll have working climate .
Car wasn't right on the drive up so i was a bit demoralised, on the way home i thought i'd disconnect the N75, upon opening the bonnet i saw it wasn't connected car was running and when i put the connector on i heard it click. i only had half a mile to home but when i gave it some, it boosted to 1.7 (might go higher but i didn't have time to take it on a longer drive)
Got lots of other little jobs to do to it but im getting there now. Can anyone confirm i need to remove the front subframe to do the sump gasket?

Glad your getting there Shaun,must be a huge relief now your boosting. It sounds like your getting stuck in so why don't you start a thread up for us URS6 boys? Will you do a thread?

[220bhp]

Shaun you will need two sump gaskets for renewal .One ether side of the baffle plate

[shaun5]

Shaun you will need two sump gaskets for renewal .One ether side of the baffle plate

I did think that when I wrote the message

[shaun5]

Glad your getting there Shaun,must be a huge relief now your boosting. It sounds like your getting stuck in so why don't you start a thread up for us URS6 boys? Will you do a thread?

I may just do that

[Vorsprung durch Technik]

Go on,do a thread.........you know you want to.

[shaun5]

Ok i thought i had sorted my boost issue but now im not sure The car goes better than it did, it shows 1.7 on the computer display. I thought this was ok but ive just taken one of my other S6's up the road and that boost to 2.1/2 on the display (that one is manual)
Could any S6 Auto owners tell me what there cars boost to is 1.7 ok because its an auto.

[shaun5]

Bump for last question

[newsh]

Should be 2.1

Is the N75 plugged in and working?

[shaun5]

even if its an auto???? its had a replacement dump vale (metal type) and i have swapped the N75 with one from a car i know is ok and yes its plugged in.
All manifold pipes have been check and are ok.

[newsh]

There's no reason why the auto should boost less than the manual AFAIK.

Have you done a proper boost leak test?

Is it possible you have a leak on the vac/boost line to the ECU?

If the small bore vac/boost lines are original they will surely be leaking.

[shaun5]

i did a mitevac check on the line to the ecu. That was all ok. Haven't done a proper boost test. i will be removing the bumper to do the cambelt change so will do the test then and see if the intercooler is ok.

Ive got a chipped ecu from a manual car i might stick in it and see if i get more boost got a standard ecu from a manual car as well.

Could it be the auto box ecu not allowing it to boost?

[squarebare]

I've an auto s6 and have only seen 1.9 on the dash so far, I haven't done a leak test yet. Interested to know if it should be higher.

[newsh]

Low boost

I'm sure if you put the ECU in a manual car or an S2 ABY coupe or Avant, it will boost to 2.1 - 2.2
Whether there's some kind of interlock with the Auto box I'm not sure.

Did you mighty vac the other small pipes?

[popdemonic]

Dave (UrS4boy) just asked me to chime in the thread about the correct boost level for an auto car.
my car originally had auto box and i did swap it to manual a few years ago.it's normal you feel the
auto is sluggish to jump out when you have another manual car.i would say the autobox is much
slower than manual especially you're trying to jump out from standstill.
ok let's talking about the low boost on your car what is the normal boost consensus on auto car?
i remember when i first got the car i also had the same question on my mind what is the max boost
i could road from the digital boost gauge.normally,if your car is bone stock.you should see 1.9bar max
most of the time and sometime when you kick down or driving the high gear(more load) with lower rpm.
you occassionally see the digital boost gauge read out 2.0-2.1bar for a few seconds and i guess that's the
overboost mode kicked in.i have seen the more of auto box urs4/s6 on this day could achieved the
max boost at 1.9bar and some cars never reached 2.1bar.from my own experiences i found my car
had this problem back on 10years ago .i had followed the instruction and some writeup about increase
more preload on spring. the top of wg by turning the top screw down for a few turns.unfortunately,that didnt
work out on my car.i had even tried to turn 14turns on the screw all the way down which normally i would have
a boost cut(exceeded) from the ecu safety feature but mine.finally i found out the stock wg spring weaken due to
being toasted with the high temp from the exhaust gas so no matter how many turns down on the top screw,
it did nothing on the boost level.i ended up getting the stiffer spring(no 1,9bar wg spring introduced back on my old day) and i could be rising the boost level
upto 2.4bar on the digital read out before motronic cut off the fuel due to the max boost exceeded(on stock ecu).
if you could only boost your car at 1.7bar max, i assume you might be having some massive boost leak somewhere.
you need to do the classic boost leak test by having the bung on the intake boot and pressurized the intake tracts.
if your car is still having all the stock vacuum hoses.i believe lot of your hoses is toasted and brittle.you will have
a lot of boost leak from those small vacuum hoses.i found a lot of vacuum hoses could not hold the boost when i first got
my car over 10years ago.under the intake manifold there's a small Tee rubber hose which is commonly brittle on the
20years old cars.so i doubt you have either a massive boost leaks or too weak wastegate spring.1,7bar is way too slow though with the 1,9bar on autobox . HTH