help narrowing down on issue plz

[nobbybonez]

hi,

2000 amk s3...
recently dropped mrs to airport, drove around 550 miles that day. drove faultlessly.
started the car the following day, and it fired up fine, but then ran rough, misfiring, no power. seemed to rev ok, but died with any load. parked up, let it warm up whilst i did a scan with a bluetooth obd reader, which gave a p0130 code.


16514/P0130/000304 - Oxygen (Lambda) Sensor B1 S1: Malfunction in Circuit
Possible Causes

• Oxygen (Lambda) Sensor Heating Bank 1 Sensor 1 faulty

Possible Solutions

• Check Oxygen (Lambda) Sensor Heating Bank 1 Sensor 1

when warm, it seemed fine, so drove the remaining distance home, ran fine. started fine the next day. the next couple of times the car was used, the same issue arose, though not as bad as the first time. again, after half a mile or so, was running fine. i have just scanned again, the p0130 code seems to have vanished (i did not clear codes) and now have p0170 in its place using the bluetooth obd and torque. with vcds, i get p17584:


17584/P1176/004470 - Bank1: O2 (Lambda) Correction Behind Catalyst: Control Limit Reached
Possible Causes

• Intake Air System leaking
• Oxygen Sensor(s) and/or Oxygen Sensor Control faulty

Possible Solutions

• Check Intake Air System for Leaks (False Air)
• Check Oxygen Sensor(s) and/or Oxygen Sensor Control (all of them!)

now i'm guessing its an o2 sensor, but believe there are more than one?
maf replaced a few months back, was smoke tested then, hoses replaced etc.

any help going forward or pinning down fault much appreciated...

 

[ayfreetee]

Maybe the wiring to the sensor is at fault.

 

[nobbybonez]

thanks, it is a possibility. i can't understand why it only runs rough for a short while if its wiring though...

 

[IPG]

IIRC bank 1 is the pre-cat lambda/sensor.

if you follow the U-bend black hose that goes in front of the charge pipe and follow it up to the firewall then look under the strut brace you will see the exhaust manifold and downpipe. there you will see the Lambda probe sticking out of the downpipe. The wiring should run to a little holder on the heat shield to where it'll plug in to a bracket on the firewall... the actual plug part should be in some heat shielding fabric (undo the heat shielding).

check wiring from the probe to the plug.

Hope that makes sense!

Also check for boost leaks. This happened to me where i would start the car. It would run ok for maybe 10 seconds... then it'd run rough and then die.

 

[nobbybonez]

awesome ian, thanks. will check it out. thanks for the advice..

 

[nobbybonez]

ok, unable to find any issue with the wiring, can someone link to a quality sensor to replace with please?
there seem to be shed loads on ecp, don't want to buy a duff 'un...

 

[nobbybonez]

ok, so i sold my *** for a new sensor, and did the swap today, no more code throwing and seems to be running fine.
i am a little concerned that the replacement sensor came without the fabric heat shield tube that protects the wiring.
the stealer gave me some self adhesive aluminium foil stuff, but wondered if there is a better solution, or if the shielding is necessary...?
thoughts?

 

[nobbybonez]