Started my car up after work, went to pull away from the parking garage and the car hardly moved. Feels like it is in limp mode even though my car/ year isn't applicable. I have absolutely no boost what so ever; I cannot even hear my turbo spool. Maintained to get home even though my car couldn't even get out of it's own way. Scanned via vagcom and received no DTCs....??? Now let me also say that my car has had inconsistent boosting issues since I got it chipped about 5k mi ago. I replaced my turbo right beforethe GIAC chip due to a bad wastegate valve. My car has been surging like crazy off and on since I got the upgraded software; was about to change the N75 valve soon due to relative surging occurence. I also have the Forge splitter DV installed along with the airbox mod. I also replaced my MAF not too long ago as well. Do you think a faulty N75 valve couldtotally wipe out my boost without any associated DTCs?How come I am not receiving any DTCs? Posted below is a copy of my scan. Any help or advice would be greatly appreciated. Thanks again guys:
Friday,15,February,2008,17:38:00:06065
VAG-COM Version: Release 704.1
Data version: 20071016
Chassis Type: 8D - Audi A4 B5
Scan: 01 02 03 08 15 16 17 25 35 37 45 55 56 57 67 75 76 77

Mileage: 147170km/91447miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 8D0-907-559-AEB.LBL
Part No: 8D0 907 557 P
Component: 1.8L R4/5VT MOTR AT D07
Coding: 06251
Shop #: WSC 06335
No fault code found.
Readiness: 0000 0000
-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 8D0-927-156.LBL
Part No: 8D0 927 156 BN
Component: AG5 01V 1.8l5VT USA 8508
Coding: 00000
Shop #: WSC 00000
1 Fault Found:
00526 - Brake Light Switch-F
27-00 - Implausible Signal
-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-111-EDS.LBL
Part No: 8E0 614 111 A
Component: ABS/EDS 5.3 QUATTRO D10
No fault code found.
-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8L0-820-043-2D.LBL
Part No: 8L0 820 043 D
Component: A4 KLIMAVOLLAUTOMAT_D75
Coding: 04142
Shop #: WSC 06335
No Faults Found
or DTCs not supported by controller
or a communication error occurred
-------------------------------------------------------------------------------
Address 15: Airbags Labels: None
Part No: 8D0 959 655 M
Component: Airbag 7 Audi 0502
Coding: 00104
Shop #: WSC 06335
No fault code found.
-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8D0-919-xxx-17.LBL
Part No: 8D0 919 910 P
Component: B5-KOMBIINSTR.UN4 D06
Coding: 02242
Shop #: WSC 85555
Part No: IMMO
Component: IDENTNR: AUZ8Z0W8070374
IMMO-IDENTNR: AUZ8Z0W8070374
No fault code found.
-------------------------------------------------------------------------------
Address 25: Immobilizer Labels: None
Part No: Bitte Adress
Component: e 17 eingeben
No Faults Found
or DTCs not supported by controller
or a communication error occurred
-------------------------------------------------------------------------------
Address 35: Centr. Locks Labels: 8D0-862-257.LBL
Part No: 8L0 862 257 N
Component: CV-Pump D10
Coding: 16140
Shop #: WSC 06335
1 Fault Found:
00955 - Key 1
09-00 - Adaptation Limit Surpassed
-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 4B0-951-173.LBL
Part No: 4B0 951 173
Component: Innenraumueberw. D03
Coding: 00101
Shop #: WSC 06335
No fault code found.
-------------------------------------------------------------------------------
Address 56: Radio Labels: None
Part No: 4B0 035 186 A
Component: Radio D02
Coding: 00201
Shop #: WSC 06335
No fault code found.
End --------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------

 

did you regap plugs?

 

Funny thing you asked highwords because I actually just purchased new NGK BKR6E plugs on the way home tonight to install thinking that my plugs may have fouled out. Can bad plugs really have this effect on an engine? I mean no boost even with the throttle floored? There are no misfires or roughness in the engine what so ever. I still do not know why I am not receiving any DTCs...

 

sounds like a stuck waste gate

 

i would say the wrong plugs can have a bad effect, but that bad, not sure....... did you hear the turbo at all? do you have a boost guage? and only 5 k on a rebuilt turbo could be a bad turbo....


maybe cincy or onepoint8 will chime in

 

Problem fixed!! Thanks turbokraut. Swapped plugs out with new BKR6Es gapped @ .028 and she runs like a champ! Wow, I had no idea faulty plugs could have that much of an effect on an engine. Before this happened I filled up with Sunoco ultra 94 and added a bottle of STP fuel injector cleaner;do you thinkthe high test could have fouled out the plugs? The Bosch platinums I had in there were in bad shape; they were the four prong type all carbon coated and black. Each one also had some oil build-up on the bottom of the porcelin..?? Along with replacing the plugs I removed all intake plumbing and associated hardware to check it out. Tried replacing my N75 valve but local Audi dealer was closed. [:@]Installed everything back to normal and she's running good. Seems to be a little more responsive and pulls more smoothly through the power band but is still surging like a b*tch! Should I upgrade to the race valve or do an mbc; heard GIAC doesn't care for the race valve...?? Any ideas?

 

you could run the j valve..... gives you more psi, but not quite as agressive as the race...... not as many problems, also not sure if this would do it, but how much are you venting atmospherically? that might be part of your surge