2.0 TDI PPD BMN Drinking Fuel

[aqibi2000]

Hi,

I've got a 2.0 TDI PPD BMN, the fuel economy has significantly plummeted, any ideas as to what to test? I have VCDS and tools.

It was DPF deleted and remapped a few years ago.

The only thing I have changed to try and rectify this is the LAMBDA sensor since the mileage of the car has just touched 100k. Thinking about cleaning the MAF.

Suggestions would be appreciated.

 

[desertstorm]

You could spend a lot of time and money changing parts before you fixed it assuming it's down to something simple that you can change. How many mpg was the car doing and what is it doing now?.
Diesel fuel economy always drops this time of the year.For many reasons.
MAF is a reasonably common issue that can usually be felt by a lack of performance. Have you checked for boost leaks, Is the engine warming up ? .

 

[aqibi2000]

Hi, I actually changed the O2 sensor since it flagged a one off error about 2 months ago (can't recall what this actually was, but just got round to installing it recently).

I'm basically getting about 50 miles to a quarter tank. The car pulls very well, no boost leaks and the engine correctly warms up to 90 degree C (confirmed via gauge and VCDS).

 

[Bugeye_bob]

CTS is cheap and can cause daft fuel issues.

 

[aqibi2000]

The coolant level sensor error goes off on cold morning (very common problem) it's just a switch really

Any particular way to test CTS since it does correctly rise to 90 degree course

 

[aqibi2000]

The coolant temperature sensor works and the thermostat operate correctly.


Any other suggestions please.

 

[desertstorm]

If you really are getting 50 miles to a quarter tank get underneath and look for the hole where the diesel is leaking out. That is very very poor fuel economy.I believe those cars were one of the first with a DPF. Is it partially blocked ? , are the brakes binding ? . Just walk around the car and feel the centre of the wheel by the bolts after a decent run. The front pair and rear pair should be the same kind of temp. The fronts usually being warmer than the rears.

 

[aqibi2000]

Thanks desertstorm I will check the fuel lines and tank (somehow), although I fuel isn't evaporating / when left for a week - occurs proportionally to how much it's driven

-The car has got a DPF Delete and Remap > the VCDS Block 68 in the video demonstrates no DPF restrictions to the ECU.
-Brakes aren't binding. If they do get slightly warm after a serious workout, they're all of equal warmth so this indicates even wear.

I couldn't upload my video to the forum as it is a .mp4 format but here is a link to one of the temperature sensors reading 1000 degree C then when throttle is applied drops down to around 250. http://sendvid.com/m4wdh4pa
( in the video the cursor is magnified to help visually see when throttle is applied since there's no audio)

I've replaced the main EGT
. From my experience this indicates a bad sensor but no idea which one the block is reading .

 

[aqibi2000]

Can anyone help identify the part number of the sensor

 

[desertstorm]

That sensor is part 17 in the following diagram.
http://audi.7zap.com/en/rdw/audi+a3+s3+sportb+lim+qu/a3/2008-638/1/145-145045/

Do you have fault codes on VCDS for the G235 sensor ?

When it's reading 1000 degrees it's because it's open circuit. A wire may be broken inside the sensor, as you rev the engine and it heats up the sensor is expanding/ wire is expanding and making contact again giving you a reading.
You need to replace the sensor, on a normal car you would get fuel cuts as the EGT protection would reduce fuel to protect the turbo. Because it is remapped I don't know what they have done with the protection maps. They may all be maxed out.
Part number would appear to be 03G906088AN or 03L906088BS

http://www.vwwatercooled.com.au/forums/f28/jazds-mini-build-thread-71699-5.html

http://www.ebay.co.uk/itm/NEW-and-G...TEMPERATURE-SENSOR-03L906088BS-/162263844030?

 

[aqibi2000]

That sensor is part 17 in the following diagram.
http://audi.7zap.com/en/rdw/audi+a3+s3+sportb+lim+qu/a3/2008-638/1/145-145045/

Do you have fault codes on VCDS for the G235 sensor ?

When it's reading 1000 degrees it's because it's open circuit. A wire may be broken inside the sensor, as you rev the engine and it heats up the sensor is expanding/ wire is expanding and making contact again giving you a reading.
You need to replace the sensor, on a normal car you would get fuel cuts as the EGT protection would reduce fuel to protect the turbo. Because it is remapped I don't know what they have done with the protection maps. They may all be maxed out.
Part number would appear to be 03G906088AN or 03L906088BS

http://www.vwwatercooled.com.au/forums/f28/jazds-mini-build-thread-71699-5.html

http://www.ebay.co.uk/itm/NEW-and-G...TEMPERATURE-SENSOR-03L906088BS-/162263844030?

Absolutely brilliant Sir You're thermal expansion explaination of the element makes perfect sense, I over looked that.

These DPF deleted cars only use the 2 sensors Lambda and Pre-Turbo EGT. So it can very much be the reason of the poor fuel economy.
I agree though it's a rubbish MAP considering it hasn't thrown a MIL for protecting the engine.


Thank you, I'll post back in a few days after replacement.

 

[hollows wife]

probably had dpf deleted with something like volta . which basically stops it throwing any codes related to the ecu .

 

[aqibi2000]

The guy did struggle trying to perform the dpf delete as it's a quattro vehicle so not as common - generic dpf delete scripts don't work with it of course...so didn't have as many tested maps

 

[aqibi2000]

Hi guys I'm unable to confirm the sensor varient as it has no markings on it at all.

I'd like to know which one to specifically buy BS/AN. I presume this depends on another factor of the car (manifold shape between the quattro and fwd).

Is anyone able to deduce this via my VIN. Thank you

Would be highly appreciated by a fellow suffering the 50 miles to a quarter tank lol

 

[aqibi2000]

Anyone got a quattro a3 (2006-2008) with the BMN Engine able to read the part number from their sensor please.