Boost Pressure A3 aum 1.8T

DenCar

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vcds data logging, block 115, has shown a actual pressure of 1440 mb (requested 1430 mb) at 5040 rpm. Most of the time throughout the rev range it is showing requested 1010 actual just a little higher.
This seems low but, the car really moves, its not slow.

Any comments would be appreciated.

DC.
 
1400 is 0.4 bar boost. ie just above atmospheric. i think the cars in limp mode
 
vcds data logging, block 115, has shown a actual pressure of 1440 mb (requested 1430 mb) at 5040 rpm. Most of the time throughout the rev range it is showing requested 1010 actual just a little higher.
This seems low but, the car really moves, its not slow.

Any comments would be appreciated.

DC.

Post a screen shot of the logs mate. I can blow 0.4 bar through a straw.
 
i need about 0.4 extra after 5krpm. wanna lay on the bonnet next time im at pod?
 
Thanks guys, something is obviously not right, will do another log-run. The car is definately not in Limp Mode and pulls strong in every gear and upto 100mph with no problem before I back off.

DC
 
if its only requesting 1400 then youre well down on boost. find someone local and see if theyll take you out in their car

im in northwich next week if youre game
 
Thanks for your offer Matt, just done another log, in 3rd gear between 2000 and to near 6000, much the same boost level, highest was 1500 mb at 3960 rpm., also i do have the vcds error code 17705 and 17545 so I do have a boost leak, i just cant understand why the car runs so well. Will get all the hoses checked etc. Ill keep your offer in mind.

DC
 
17705 Pressure Drop between Turbo and Throttle Valve
17545 - Fuel Trim: Bank

blatently and its dropping into limp mode. youll need to go over the intake system front to back. i normally go armed with every sized jubilee clip and silicon hose imaginable!

shouldnt be too hard, the system isnt as overly complicated as it looks once you get your head around it
 
Yep I did think of that but have ordered a hose kit from dpm, so ill fit them and see if it cures the leak.

Thanks

DC
 
guys, why is everyone jumping to conclusions?

he's already said it's making 0.5 bar boost, that's 7psi, which is standard for an AUM..........

Doesn't sound like there's anything wrong with it to me....
 
he said most of the time through the rev range it shows 1010
 
I don't want to be rude here, but I think the chap is logging incorrectly.

''most of the time'' to me sounds like driving around normally, during which the ECU will request very little boost so 1010 sounds about right.

if he's done a WOT run from 2-6k and it's peaked at 0.5 bar at just under 4krpm, then that sounds about right to me.

I'm not suggesting it's problem free, I'm yet to see an untouched 1.8T with a working DV and a non split PCV, I just don't think it's running as badly as everyone else seems to think.

being an AUM with a map sensor, to some degree it'll work the turbo to try and maintain boost levels, compared to an AGU which will just see normal maf logs but rich fuelling and pull some fuel out.
 
youre just being harsh :p

well see what he comes back with
 
This is part of the second log I did, dont really know what it all means, just to reiterate, the car runs great and pulls like hell, on a motorway in 5th and at just above 40 mph it pulls with no problem.

Tuesday;03;August;2010;18:18:10
06A 906 032 HJ;;1,8L R4/5VT 0002;
;Group A:;'115;;;;Group B:; Not Running;;;;Group C:; Not Running
;;Engine Speed;Engine Load;Boost Pressure;Boost Pressure;;;;;;;;;;
;TIME;(G28);;(specified);(actual);TIME;;;;;TIME;;;;
Marker;STAMP; /min; %; mbar; mbar;STAMP;;;;;STAMP;;;;
;0,28;2440;56,4;1000,0;1090,0;;;;;;;;;;
;0,58;2480;66,9;1130,0;1120,0;;;;;;;;;;
;0,89;2520;84,2;1400,0;1250,0;;;;;;;;;;
;1,19;2640;100,8;1500,0;1390,0;;;;;;;;;;
;1,49;2720;110,5;1520,0;1520,0;;;;;;;;;;
;1,79;2800;112,0;1550,0;1530,0;;;;;;;;;;
;2,09;2880;114,3;1540,0;1550,0;;;;;;;;;;
;2,39;3000;115,0;1520,0;1550,0;;;;;;;;;;
;2,70;3080;115,8;1510,0;1550,0;;;;;;;;;;
;3,00;3160;114,3;1500,0;1510,0;;;;;;;;;;
;3,30;3240;114,3;1480,0;1510,0;;;;;;;;;;
;3,60;3360;115,0;1480,0;1490,0;;;;;;;;;;
;3,90;3440;115,8;1470,0;1480,0;;;;;;;;;;
;4,21;3520;115,0;1490,0;1480,0;;;;;;;;;;
;4,51;3600;114,3;1480,0;1480,0;;;;;;;;;;
;4,81;3720;112,8;1490,0;1480,0;;;;;;;;;;
;5,11;3760;112,8;1490,0;1480,0;;;;;;;;;;
;5,41;3880;112,8;1500,0;1490,0;;;;;;;;;;
;5,72;3960;112,8;1500,0;1500,0;;;;;;;;;;
;6,03;4040;112,0;1490,0;1490,0;;;;;;;;;;
;6,32;4120;111,3;1490,0;1490,0;;;;;;;;;;
;6,62;4200;110,5;1480,0;1480,0;;;;;;;;;;
;6,92;4280;110,5;1470,0;1480,0;;;;;;;;;;
;7,23;4360;110,5;1480,0;1470,0;;;;;;;;;;
;7,53;4440;109,8;1470,0;1460,0;;;;;;;;;;
;7,83;4520;111,3;1450,0;1460,0;;;;;;;;;;
;8,14;4600;109,8;1460,0;1440,0;;;;;;;;;;
;8,44;4680;110,5;1470,0;1450,0;;;;;;;;;;
;8,74;4720;111,3;1460,0;1460,0;;;;;;;;;;
;9,03;4800;109,8;1450,0;1450,0;;;;;;;;;;
;9,33;4880;110,5;1440,0;1440,0;;;;;;;;;;
;9,64;5000;109,8;1430,0;1430,0;;;;;;;;;;
;9,94;5040;110,5;1430,0;1440,0;;;;;;;;;;
;10,24;5120;109,8;1410,0;1430,0;;;;;;;;;;
;10,54;5200;109,0;1380,0;1420,0;;;;;;;;;;
;10,84;5240;109,0;1390,0;1400,0;;;;;;;;;;
;11,15;5320;107,5;1350,0;1390,0;;;;;;;;;;
;11,46;5400;106,8;1340,0;1370,0;;;;;;;;;;
;11,76;5440;105,3;1320,0;1360,0;;;;;;;;;;
;12,05;5520;100,8;1320,0;1350,0;;;;;;;;;;
;12,36;5560;97,0;1320,0;1340,0;;;;;;;;;;
;12,66;5600;98,5;1330,0;1290,0;;;;;;;;;;
;12,97;5680;103,8;1340,0;1330,0;;;;;;;;;;
;13,27;5720;103,0;1350,0;1340,0;;;;;;;;;;
;13,57;5760;103,8;1320,0;1330,0;;;;;;;;;;
;13,87;5840;103,0;1320,0;1330,0;;;;;;;;;;
;14,17;5880;100,8;1310,0;1330,0;;;;;;;;;;
;14,47;5960;99,2;1300,0;1320,0;;;;;;;;;;
;14,78;6000;101,5;1220,0;1320,0;;;;;;;;;;
;15,08;6040;93,2;1210,0;1290,0;;;;;;;;;;
;15,38;6040;87,2;1180,0;1300,0;;;;;;;;;;
;15,68;6080;83,5;1180,0;1300,0;;;;;;;;;;
;15,98;6120;79,7;1170,0;1300,0;;;;;;;;;;
;16,28;6160;77,4;1170,0;1290,0;;;;;;;;;;
;16,59;6160;75,2;1170,0;1310,0;;;;;;;;;;
;16,89;6200;74,4;1000,0;1320,0;;;;;;;;;;
;17,19;6160;39,8;1000,0;1230,0;;;;;;;;;;
;17,49;6080;20,3;1000,0;1170,0;;;;;;;;;;
;17,79;6080;17,3;1000,0;1110,0;;;;;;;;;;

DC
 
Last edited:
Thanks matt...so if as prawn thinks, its about the right pressure and , vag-com is showing a pressure loss then it must be a small leak and replacing the hoses (5 hose kit ordered) will plug the leak and give better log figures.

DC
 
youre actually exceeding requested boost some of the time