Poor performance and high fuel consumption

[drurydd1]

Hi All,

long time reader, first time poster.

My Mk5 golf had it's catalytic converter replaced last week and all seemed fine when i picked the car up Friday.  Monday morning on the way to work i noticed the exhaust systems warning light had come on.  When i got to work i connected up my vcds and found the following fault, 17861 - Exhaust Gas Temp Sensor 1 (G235) i cleared the fault as i thought maybe the sensor wasn't used to a brand new catalytic converter.  On the way home it came back on and i ignored it until Thursday when things got relay bad. 

All week it was burning through petrol 3/4 of a tank in 3 days and it was slow to accelerate, you could feel the engine struggling (very slight) and on Thursday i stopped at the traffic lights and when i tried to move off the engine stalled for no reason at all.  After that when i was driving down the road at 60 i felt a slight shudder and the car very slowly started to loos power.  I dropped into 5th gear and started to stab at the accelerator to try and get the engine to maintain power.  after about 5 -10 seconds i felt another slight shudder and the engine started to accelerate.  I took the car to my local garage for them to look at and they have no idea even after i showed them my vcds print out, they advised me to take it to the VW specialist.  Below is the up to date scan from vcds.  Does anyone have any suggestions before i book it in to VW.  Any suggestions will be very much appreciated. 

Address 01: Engine        Labels: 03C-906-056-BAG.lbl
   Part No SW: 03C 997 056 M    HW: Hardware No
   Component: MED9.5.10       G00 9265 
   Revision: 00000000    Serial number: VWZ7Z0D9259848
   Coding: 0000072
   Shop #: WSC 00864 210 72125
   VCID: 3753CB6D46F395A0D06

4 Faults Found:
17861 - Exhaust Gas Temp Sensor 1 (G235)
            P1453 - 001 - Open or Short to Plus - MIL ON
18354 - Control Module 1 for Coolant Fan
            P1946 - 004 - Defective - Intermittent
16575 - Fuel Pressure Sensor (G247)
            P0191 - 008 - Implausible Signal - Intermittent
16475 - Valve for Fuel Metering (N290)
            P0091 - 002 - Short to Ground - Intermittent
Readiness: 0000 0000

Thanks
Douglas

[edd666999]

What happened after clearing the codes?

Have you searched for G235 or G247 on this forum? Loads of info on varying issues.

[drurydd1]

When i clear the faults with vcds they come back on after about 10 miles but the car still feels like it is struggling.  I did do some research in to the faults codes but 9/10 times I didn't find what i was looking for or didn't understand.  I just wondered if anyone had had a similar problem.  But the car is booked in to VW for 4th of July, back to the old bus.   

[pandahouse68]

why did u replace the Catalytic Converter

[drurydd1]

The was one of the fault codes that got fixed the other week and it was all broken up inside when the mechanic showed me after he replaced it. 

[pandahouse68]

Could u tell me what fault code it was 

[drurydd1]

Sure it was, see below.  I was told the fault code cleared itself when the car was started after the new one was fitted.

16804 - Catalyst System; Bank 1
            P0420 - 002 - Efficiency Below Threshold - MIL ON

[pandahouse68]

I have the same fault code P0420, just wondering if I need to replace the CAT like u did

How much for a new CAT ,mate

[drurydd1]

I was £300 for the cat + time and vat came to £444 quit a lot really.  Part is VK6087T you might be able to get one for less. Hope that helps you.

[Scottymon]

You can grab second hand standard Downpipes for about 50 quid.

[pandahouse68]

You can grab second hand standard Downpipes for about 50 quid.

really ,where from, please PM me 

[Scottymon]

The downpipe obviously comes with pre-cat, flexi and MAIN CAT which is why I mentioned it. 
Grabbed mine for £50 off a forum member and banged out the pre-cat, then gave it to the garage to fit, it seemed easier, rather than chiseling out pre-cat at the garage. Removing the exhaust on the drive, didn't appeal to me, lol.