Bora Economy Far Too Low!

[waynehudd2]

hi you lot, been asking lately about the 1.8t swap and have had a few good responses to that, but until i start that iv had a major decline in the mpg of my 2.0l 8v.

iv read up on parkers and going by that at new my car should of been doing around 411 miles to a tank.

when i got the car around 2 years ago i was getting about 350 before the fuel light came on which i was quite happy with.

now though i am running at around 20mpg which is costing me an arm and a leg in fuel.

iv had the head gasket replaced and iv also done the spark plugs and ht leads.

i own a copy of vag com and am getting fault coeds up for example:

random/multiple misfire
cylinder short to ground
lambda sensor voltage too high

i am not sure exactly the other codes or the correct wording right now but i can get them once i get the log from my laptop...

just wondering what people are thinking about this and weather or not there are very common problem that i could look at....

thanks waynehudd2

 

[herb]

mate you need to post the exact fault codes
cause only a few weeks ago i had your first fault but it also gave me the code for the cylinder it was happening on (coil pack by the way)

 

[waynehudd2]

these are the dtc's from vag com. i have done a couple of scans and cleared the codes each time to see how intermittent they are. i have just ordered a new coilpack just to eliminate that to hopefully that will arrive soon. the car is still very slugish on getting up to speed but runs ok once there...

Thursday, 13 May 2010, 19:11:44

VAG-COM Version: Release 409.1-US



Control Module Part Number: 06A 906 018 EF

Component and/or Version: 2.0l R4/2V MOTR HS V04

Software Coding: 00031

Work Shop Code: WSC 01317

10 Faults Found:

16523 - Oxygen (Lambda) Sensor B1 S2: Response too Slow

P0139 - 35-00 - -

17536 - Long Term Fuel trim system too lean (bank 1)

P1128 - 35-00 - -

16555 - Fuel Trim System Too lean (bank 1)

P0171 - 35-10 - - - Intermittent

16522 - Oxygen (Lambda) Sensor B1 S2: Signal too High

P0138 - 35-10 - - - Intermittent

17633 - Cylinder 1 fuel injector circuit short to ground

P1225 - 35-10 - - - Intermittent

17634 - Cylinder 2 fuel injector circuit short to ground

P1226 - 35-10 - - - Intermittent

17635 - Fuel Injector for Cylinder 3 (N32): Short to Ground

P1227 - 35-10 - - - Intermittent

17636 - Cylinder 4 fuel injector circuit short to ground

P1228 - 35-10 - - - Intermittent

17833 - Tank Ventilation valve short to ground

P1425 - 35-10 - - - Intermittent

16518 - Oxygen (Lambda) Sensor B1 S1: No Activity

P0134 - 35-10 - - - Intermittent

---------------------------------------------------------------------------





Saturday, 15 May 2010, 14:27:02

VAG-COM Version: Release 409.1-US



Control Module Part Number: 06A 906 018 EF

Component and/or Version: 2.0l R4/2V MOTR HS V04

Software Coding: 00031

Work Shop Code: WSC 01317

6 Faults Found:

16518 - Oxygen (Lambda) Sensor B1 S1: No Activity (means bank 1 sensor 1)

P0134 - 35-10 - - - Intermittent

16684 - Random misfire detected any cylinder

P0300 - 35-10 - - - Intermittent

16685 - Cylinder 1 misfire detected

P0301 - 35-10 - - - Intermittent

16687 - Cylinder 3 Misfire Detected

P0303 - 35-10 - - - Intermittent

16688 - Cylinder 4 misfire detected

P0304 - 35-10 - - - Intermittent

16522 - Oxygen (Lambda) Sensor B1 S2: Signal too High

P0138 - 35-00 - - -

---------------------------------------------------------------------------





Saturday, 15 May 2010, 21:38:50

VAG-COM Version: Release 409.1-US



Control Module Part Number: 06A 906 018 EF

Component and/or Version: 2.0l R4/2V MOTR HS V04

Software Coding: 00031

Work Shop Code: WSC 01317

3 Faults Found:

16522 - Oxygen (Lambda) Sensor B1 S2: Signal too High

P0138 - 35-00 - -

16518 - Oxygen (Lambda) sensor B1 S1: No Activity Detected
P0134 - 35-00 - -

17536 - Shareware Version. To Decode all DTCs

P1128 - 35-00 - Please Register/Activate (long term fuel trim B1 System too lean)

---------------------------------------------------------------------------





Wednesday, 02 June 2010, 14:42:08

VAG-COM Version: Release 409.1-US



Control Module Part Number: 06A 906 018 EF

Component and/or Version: 2.0l R4/2V MOTR HS V04

Software Coding: 00031

Work Shop Code: WSC 01317

3 Faults Found:

16523 - Oxygen (Lambda) Sensor B1 S2: Response too Slow

P0139 - 35-00 - -

16522 - Oxygen (Lambda) Sensor B1 S2: Signal too High

P0138 - 35-00 - -

16518 - Oxygen (Lambda) sensor B1 S1: No Activity Detected
P0134 - 35-00 - -

---------------------------------------------------------------------------


obviosly theres alot of different codes, iv been tol the lambda sensors could be out due to an affect of the missfires but to be honest dont know much about the in depth engine problem stuff

 

[obi_waynne]

Not sure on this engine so I'm guessing here but....

I'd be tempted to get another Lambda sensor from a breakers yard if only to diagnose that and rule it out.

Ignition lead,coil pack and injector could be the issue. Swap over the leads (obviously don't switch them and retain the correct firing order starting with cylinder 1 and replacing leads one at a time).

Oh and disconnect and reconnect the earth lead. Sometimes it can be a simple as that!

 

[pgarner]

the 2.0 has an ignition amplifier does it not, these are common to go hense why they were dropped. they are normally found on the side of the airbox

also not sure if you can record maf logs (group 2 under engine iirc) on the shareware version but if you can do a couple of runs in 2nd gear you should see around 90gms. MAF might not show as faulty but not be reading correctly causing inproper a/f
if you do seem out of spec then disconnect it and see how it runs

also worth doing fuel trim checks (google them as i cant remember been a while since i last done them)