MK4 Golf GTI 1.8t AUM (same as mk1 octavia vrs?) - Fault Codes

[Fabia93]

So my cousin called me up to say his golf has been playing up alot recently, he has had a audi mechanic look at it and alot another specialist mechanic however the problem keeps happening and he doesn't want to keep spending out money unless it will fix the problem. I purchased VCDS from Gendan the other day so popped out to have a wee look this morning and see if I could help. bunch of fault codes have popped up which I will copy in a comment.  He has been told he needed a few things so had to get a new turbo and some new lambda's also fitted not sure what else he has had done.

 

I have a feeling it's something either to do with throttle body(because of the codes) or the MAF as I hear these are a common thing to go?

 

I don't want to go ahead an do something if that's not going to fix it but I understand I may have to do some trial and error.

 

If more test need to be run I am happy to do so but may need some explanation of how to do them as I only got VCDS the other day and still figuring it all out.

 

Many Thanks in Advance

[Fabia93]

Sunday,08,March,2015,07:25:10:07140
VCDS Version: Release 14.10.1 (x64)

                Address 01: Engine       Labels: 06A-906-032-AUM.lbl
Control Module Part Number: 06A 906 032 HJ
  Component and/or Version: 1.8L R4/5VT         0002
           Software Coding: 11500
            Work Shop Code: WSC 14391  
           Additional Info: WVWZZZ1JZ3W134680     VWZ7Z0B5532597
                      VCID: 6DD1F0A3278A1A49B56-515E
9 Faults Found:

17579 - Angle Sensor 2 for Throttle Actuator (G188) Implausible Signal
            P1171 - 35-10 -  - Intermittent
17967 - Throttle Body (J338)
            P1559 - 35-10 - Fault in basic settings - Intermittent
17972 - Throttle Actuator (J338)
            P1564 - 35-10 - Under-Voltage during Basic Setting - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
            P0300 - 35-00 -
16685 - Cylinder 1
            P0301 - 35-00 - Misfire Detected
17584 - Bank1: O2 (Lambda) Correction Behind Catalyst
            P1176 - 35-10 - Control Limit Reached - Intermittent
16687 - Cylinder 3
            P0303 - 35-00 - Misfire Detected
16686 - Cylinder 2
            P0302 - 35-00 - Misfire Detected
17536 - Fuel Trim; Bank 1 (Mult)
            P1128 - 35-00 - System too Lean

Readiness: 0000 0000
 

[Fabia93]

Nothing from anyone?

[TeflonTom]

Start by swapping the ignition coil from cylinder 1 and 2 and see if the missfire changes cylinder.

[freelanderman]

I think the clue is in the lasr fault code, system to lean, have a good look at all the vacuum hoses for leaks, put a vacuum gauge on the car at idle, you should see 18-21 inches of vac.holding steady. Test ccomponents before replacing them. VCDS is only a starting point in diagnostics dont take everything it tells you as gospel.