vacuum pressures for turbo Octavia 110 mk1 hatch ASV

[Bornjoyful]

Having trouble - turbo not kicking in.

Low boost pressure is the code.

 

Works fine (seemingly or better ) when hardwired turbo through Mitty Vac.

 

My mechanic has never worked on this engine and he is leaning towards it not being the turbo itself although it could be just sticky vanes so he has asked me to ask a few questions.

 

1) Is the  pressure for the vacuum pump  meant to be 15-21psi?  This is what he gets.

 

2) can anyone tell us the vacuum operating pressures for the EGR, the N75 valve and the turbo itself  as Brian the mechanic cannot find that info?

 

3) can anyone show us a photo from the engine bay/  bulkhead of how it all connects just incase someone has been under there previously and done something wrong?

 

He has hardwired the turbo to his Mitti Vac and driven and it  all works fine .

He is googling Mr Muscle tomorrow but not convinced it is sticky vanes.

 

I got a new Garret turbo for £250  for him to put in but he does not want to  spend all that time  if the current turbo is ok and it is a pipe or hose or connection or something simples

 

many many thanks in advance

 

[KenONeill]

11 hours ago, Bornjoyful said:

Having trouble - turbo not kicking in.

Low boost pressure is the code.

Is the car black smoking? I've had a popped boost pipe and got heavy black smoke plus a total lack of power.

[Bornjoyful]

no smoking black or otherwise

[KenONeill]

41 minutes ago, Bornjoyful said:

no smoking black or otherwise

Well, that suggests to me that the car's not over-fuelling and you don't have a boost leak. Have you tried a VCDS diagnosis, because that strikes me as being a better way of diagnosing a faulty valve than trying to measure it's operating pressure. A for Audi are good, near you, and handy for the Blue Train lines.

[Bornjoyful]

yes we had a VW diagnosis guy yesterday and it threw up the same fault code as on the OBD.

I was told it said  'low boost pressure' - do you need an exact code number?

[Bornjoyful]

here is the report from yesterday- gobbldygook to me and is giving me palpitations! I suppose that it is the 

 

17964 code which  on googling is

17964/P1556 - Charge Pressure Control: Negative Deviation

• Boost Pressure too Low.
• Hoses/Pipes incorrect connected, disconnected or leaking.
• Charger Pressure Control defective. VNT (variable nozzle turbo): nozzles stuck.
• Solenoid Valve for Boost Pressure Control (N75) defective.

N75 just changed but couldstill  be faulty .  Still looking for any hoses or pipes that are an issue -most have been  changed now and Mr Muscle being tried asap

 

Thursday,03,June,2021,19:44:22:64069
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 21.3.0.0 (x64)  HEX-NET2 CB: 0.4543.4
Data version: 20210226 DS325.0


Chassis Type: 1U (1U - Skoda Octavia (1997 > 2011))
Scan: 01 02 03 08 15 16 17 19 22 29 35 36 37 39 46 56 76
 
VIN: TMBBP21UX32676885   Mileage: 160700km-99854miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: Redir Fail!
   Part No: 038 906 012 CL
   Component: 1,9l R4 EDC 0000SG  3359  
   Coding: 00002
   Shop #: WSC 31480  
   VCID: 5CEAFFFADF3423BBB3B-4B1E
   TMBBP21UX32676885     SKZ7Z0B1442132

2 Faults Found:
18062 - Please check DTC Memory of Instrument Cluster
            P1654 - 35-10 -  - Intermittent
17964 - Charge Pressure Control
            P1556 - 35-10 - Negative Deviation - Intermittent
Readiness: N/A

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 1C0-907-37x-ASR.lbl
   Part No: 1C0 907 379 K
   Component: ASR FRONT MK60      0103  
   Coding: 0021505
   Shop #: WSC 31480 000 00000
   VCID: 32367142E830C5CB497-5184

1 Fault Found:
00668 - Supply Voltage Terminal 30
            008 - Implausible Signal - Intermittent

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 1Ux-907-044.lbl
   Part No: 1U1 907 044 A
   Component: CLIMATRONIC     C 2.0.0  
   Coding: 11000
   Shop #: WSC 31480  
   VCID: 30327B4AE33CF7DB3F3-5160

2 Faults Found:
00532 - Supply Voltage B+
            07-10 - Signal too Low - Intermittent
01274 - Air Flow Flap Positioning Motor (V71)
            37-10 - Faulty - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 1C0 909 605
   Component: 0L AIRBAG VW51 0B   0004  
   Coding: 12364
   Shop #: WSC 31480  
   VCID: 6194CE0EF8560E53E0D-513C

1 Fault Found:
00532 - Supply Voltage B+
            07-10 - Signal too Low - Intermittent

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 1U0-920-xxx-17.lbl
   Part No: 1U0 920 911 F
   Component: KOMBI+WEGFAHRSP VDO V07  
   Coding: 23412
   Shop #: WSC 31480  
   VCID: 32367142ED30C5CB497-513C
   TMBBP21UX32676885     SKZ7Z0B1442132

2 Faults Found:
00562 - Sensor for Oil Level/Temperature (G266)
            30-00 - Open or Short to Plus
01304 - Radio
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels: 6N0-909-901-19.lbl
   Part No: 6N0 909 901
   Component: Gateway K<->CAN    0001  
   Coding: 00006
   Shop #: WSC 31480  
   VCID: 70B2BB4A23BCB7DB7F3-513C

1 Fault Found:
01304 - Radio
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 1C0-959-799.lbl
   Part No: 1C0 959 799 B
   Component: 3Y Komfortgerát HLO 0003  
   Coding: 00259
   Shop #: WSC 31480  
   VCID: 363E4D520158D9EB65F-4B1E

   Subsystem 1 - Part No: 1U6959802D
   Component: 3Y Tõrsteuer.FS KLO 0004  

   Subsystem 2 - Part No: 1U6959801D
   Component: 3Y Tõrsteuer.BF KLO 0004  

   Subsystem 3 - Part No: 1U0959811D
   Component: 3Y Tõrsteuer.HL KLO 0004  

   Subsystem 4 - Part No: 1U0959812D
   Component: 3Y Tõrsteuer.HR KLO 0004  

6 Faults Found:
01330 - Central Control Module for Central Convenience (J393)
            53-10 - Supply Voltage Too Low - Intermittent
01331 - Door Control Module; Driver Side (J386)
            53-10 - Supply Voltage Too Low - Intermittent
01340 - Mirror Adjustment Switch
            27-10 - Implausible Signal - Intermittent
01332 - Door Control Module; Passenger Side (J387)
            53-10 - Supply Voltage Too Low - Intermittent
01333 - Door Control Module; Rear Left (J388)
            53-10 - Supply Voltage Too Low - Intermittent
01334 - Door Control Module; Rear Right (J389)
            53-10 - Supply Voltage Too Low - Intermittent

End----------(Elapsed Time: 04:00, VBatt start/end: 12.2V/12.2V)-----------
 

 

 

[KenONeill]

@Bornjoyful - Well, sticky turbo vanes are common on this engine, but more usually show up as an overboost code, limp mode, and reset every time you switch the engine off.

[bigjohn]

Lots of low voltage messages - is the battery ok? Might be relevant re N75 solenoid control etc.

 

Vacuum pipes can cause issues as well - rigid pipes rub through with vibration, flexible pipes rot. It's sometimes not obvious.

 

 

[Bornjoyful]

battery new

alternator changed and good

 

N75 seems ok but wait there is a  control for that N75?- photo of wher please?

I guess Brian wanted to know the psi (or inHg  for each component so he could put the mikki on and not have to change every single bloody pipe

[J.R.]

2 hours ago, bigjohn said:

Lots of low voltage messages - is the battery ok? Might be relevant re N75 solenoid control etc.

 

Vacuum pipes can cause issues as well - rigid pipes rub through with vibration, flexible pipes rot. It's sometimes not obvious.

 

 

And also they can collapse under vacuum when hot, I had an Alhambra that would lose boost when towing a trailer & racecar in hot weather and/or on long uphill motorway sections, whenever the heat got above a certain threshold, cycling the ignition would vent the vacuum, boost would return but for shorter & shorter time intervals.

 

I would have find some way of extending the vacuum pipes to the cabin & putting a guage between the operating valve & the turbo, you could even have someone manually operate it with a Mytivac when it should be boosting.

[KenONeill]

12 hours ago, Bornjoyful said:

battery new

alternator changed and good

Well, clear down the codes, and then see which, if any, of them recur. I've had loads of codes from more or less everything caused by a sticky alternator clutch pulley sticking "open", leading to low charge. The pulley was replaced, and none of the codes recurred after being cleared.

[Bornjoyful]

Getting somewhere....

[Bornjoyful]

EGR almost totally blocked!!

[Bornjoyful]

Anyone know what happened to Lofty79?

Want to thank him for his Mr Muscle thread.

So despote this being an underboost, the actuator was  stiff and there was a lot of carbon.

brian spent upwards of 10 hrs changing all the vacuum lines , cleaning MAF, MAp and intercooler pressure sensor.

There were a couple of holes (tiny ) in the intercooler [pipe now epoxyed.

N75 ok.

 

Did Mr Muscle once and  the turbo whined  which is forst sign of life from it since I bought the car.

Today Mr muscle again and BINGO we have power!

 

BOOST

 

Then Brian installed a 130bph ECU that had been in a freinds old ASV octavia and  now it all seems to be working fine.

 

Many thanks to all who chipped in  and I am off to add to Loftys old Mr Muscle thread

 

First time I have had a properly working vehicle since i bought it!