vaccum on boost gauge

[rsmith]

This is my reading

 

[LEE69]

Yeah as above my gauge is PSI yours is BAR.

 

[BoomhaueR]

Your gauge measures BAR. Yours says nearly -0.8BAR. Convert this and you get -0.8 bar = -23.623 986 456 923 49 inch of mercury [0 °C]. Therefore you do not have a boost leak.

So to clarify if you are running around -20inHg OR -0.8BAR then you have a leak free system!

 

[bainsycupra]

vaccum

sorry just had a look and its sitting on -7 bar does that seem low.

 

[bainsycupra]

vaccum

any one know if -7 is low.do i need to get pressure tested.

 

[LEE69]

You should be fine with that, for all you know, the gauge might be faulty.

 

[Faisal]

im at -20psi on idle.

iv always suspected a boost leak since it only holds at 12/14/16psi in 2nd/3rd/4th gear respectively (on a stage 2 cupra r from 5k revs onwards) i dont know if thats normal or leakage...

 

[sambryant]

do i have a leak?
at full temp the gauge shows 0.6 to 0.7 bar
here is a pic

any help would be fab

 

[ThackersLCR]

Sorry to bring an old thread up (getting good at this). My in-hg, varies on idle. From cold it sits at -16, little tap of the peddle and drops to -20, then pull away and itl drop to -25 at the end of the road. Then back up to -20. It does this when hot or cold. Id of thought it would of stayed at the same number when up to temp? Can anyone comment?
Cheers

 

[Joeb]

good thread.

mines just about sits on -1 psi - or usually just 0 on idle

this is 100% boost leak right??

 

[turbin]

good thread.

mines just about sits on -1 psi - or usually just 0 on idle

this is 100% boost leak right??

Should have 8-9psi or 18-20inHG vacuum at idle....

 

[Joeb]

sometimes turbo engines just do my nut in lol.

i think its time for one of these smoke tests

 

[ThackersLCR]

good thread.

mines just about sits on -1 psi - or usually just 0 on idle

this is 100% boost leak right??

I would say boost leak is most likely! Have a good look under the bonet mate, most things can be spotted, build up of dirt on pipes, splits, worn areas, loose clips.

Could it be possible that my varying issue is coil pack related? Just had them out and inspected. The one i havent replaced (replaced before i got car) smells abit suspect and has a brown stain on the inside.

 

[DJ-LIAMC]

Just been out for a drive and noticed i lost boost only boosting at 13psi holding with no peak? used to be 22psi peak holding 18/19psi? also noticed vacuum on idle is now -26 and used to be -20. could this be a boost leak or hardware failure ie. MAF, N75?

 

[Faisal]

Just been out for a drive and noticed i lost boost only boosting at 13psi holding with no peak? used to be 22psi peak holding 18/19psi? also noticed vacuum on idle is now -26 and used to be -20. could this be a boost leak or hardware failure ie. MAF, N75?

im on the same boat, last night my car stopped boosting at 22psi and its only reaching 16psi. we fiddled about with my n75 and now im boosting at 4psi lol. think i need a new one...

 

[DJ-LIAMC]

damn dont sound good what did you do to the n75 to make it do that?

 

[LEE69]

There is a screw on it you can adjust.

 

[Faisal]

i did what lee just said. adjusted the screw - which made it worse lol. turned it clockwise one half turn, boosted at 8psi, turned it back, now its boosting at 4psi. turned it back round the other way, still 4 psi. im truely buggered now

 

[DJ-LIAMC]

Oh k i better leave mine then. had a look for a leak but couldnt find one next is to take it for a drive with the maf disconnected then the n75 see if its any of them

 

[DJ-LIAMC]

Ok so my boost problem fixed itself last night? boosting fine now? dont get why .