cuatronoza

This is my 01 A4 2.8 quattro tiptronic, This morning the car had crank no start, so I didn't had time to mess with it.(had to get my rx7 started up to get to work).
Now I tried to started again and it started up but with EPC, ABS, Check Engine, and Traction control lights On. engine idling at 1200 rpm and the gas pedal doesn't work, cant rev the engine and the pedal sinks to floor compared to when it was firm.
So I turn it off about 3 min of idling and there's a loud thicking noise from the area under neat the steering column for about 4 sec. Then I turn it on again and same stuff- all warning lights on. This time I turn it off and take the key off and engine is still idling but no rpm signal, I had to insert the key and cycle it to turn it off.
Then its back to crank no start.
I really need your help in what direction to go, Its my daily driver. Has anyone experienced this?? It was running perfect until today.

4Driver4

Pull codes, post codes, clear codes, drive car, see what comes back, post additional codes.

cuatronoza

Today I got hold of a windows xp laptop to try the ebay vag com I had for a while now. Got it working and was able to pull two codes
on auto trans and abs I get the same message "powertrain data bus: missing from ECU"
when I try to access the engine thru vag com I get a window that says "no response from controller"
Also I can not erase these codes, under auto trans I hear the brake switch on the shifter every time I click erase, and under abs I get the parking BRAKE light blink but the codes dont erase. The car still cranks, no start.
Possible Bad ECU?? heres a snapshot

cuatronoza

I performed a module scan and these are the onlyones I can connect to

Address 02: Auto Trans
Protocol: KW1281
Controller: 8D0 927 156 AT
Component: AG5 01V 2.8l5V USA 3132
Coding: 00002
Shop #: WSC 06435

Address 03: ABS Brakes
Protocol: KW1281
Controller: 8D0 907 389 E
Component: ABS/ESP allrad D46
Coding: 04297
Shop #: WSC 06435

Address 08: Auto HVAC
Protocol: KW1281
Controller: 8D0 820 043 P
Component: A4 KLIMAAUTOMAT D58
Coding: 00160
Shop #: WSC 06435

Skipping Address 15-Airbags

Address 17: Instruments
Protocol: KW1281
Controller: 8D0 920 980 Q
Component: B5-KOMBIINSTR. VDO D12
Coding: 02262
Shop #: WSC 40216

Address 33: OBD-II
Protocol: ????
Controller: OBD-II/EOBD, Protocol Keyword: $0808

Address 35: Centr. Locks
Protocol: KW1281
Controller: 8L0 862 257 N
Component: CV-Pump D11
Coding: 16140
Shop #: WSC 06435

Address 45: Inter. Monitor
Protocol: KW1281
Controller: 4B0 951 173
Component: Innenraumueberw. D03
Coding: 00101
Shop #: WSC 02101

Address 55: Xenon Range
Protocol: KW1281
Controller: 4B0 907 357
Component: LEUCHTWEITEREGLER D004
Coding: 00012
Shop #: WSC 06435

Address 56: Radio
Protocol: KW1281
Controller: 8D0 035 195 A
Component: Radio D00
Coding: 00110
Shop #: WSC 06435

4Driver4

I bet you have corrosion somewhere. Check the harness connections by the transmission.