Missing on A4 sport tdi AWX code

**Stunner** · 08-04-2009,09:10 PM

Hiya guys please help

I have just bought an audi a4 tdi 130bhp awx engine code. the problem i have is when boosting or putting me foot down the car did not pick up like a 130 bhp. it has a chip to boost power to 155bhp but it did not feel like 155bhp. the turbo was kicking in after 2200rpm. but now as i have removed the chip the car got its power back it actually fells like a 130bhp. but the problem i have now is that it is chucking out black smoke alot of turbo lag and the turbo is only kicking in at 3000rpm. when i put the chip back in it is still smoking. but now i have discovered that the sensor part number 0281002401 which after checking on google says its a boost sensor which is connected in the intercooler pipes at the top when disconnecting the clip from the sensor the car has no power there but the smoke has stopped when i add the clip or reconnect the sensor it becomes smoky and has miss on the engine aswell. can anybody help?

**Stunner** · 08-04-2009,09:11 PM

the chip is from a company called tdi tuning.

**benjie** · 08-04-2009,10:20 PM

If you're only getting boost from 3k rpm, I'd say change the MAF, it's the sensor plugged into the air pipe that runs from the intake to the airbox (I think, not too familiar with the layout on the A4 130tdi - despite having one myself!)

**Stunner** · 09-04-2009,12:31 AM

i bought a new maf it hsnt cured the problem.

**benjie** · 09-04-2009,12:34 AM

Could you try changing the boost sensor? What year/mileage is the car?

**Stunner** · 09-04-2009,12:43 AM

no not tried that, could that be the problem? i just wanted to know if anybody else had the same problem as mine.

**Stunner** · 09-04-2009,12:44 AM

its a 2001 51 plate TDI sport mileage 105,000.

**benjie** · 09-04-2009,01:04 AM

It certainly does sound as if the problem was partially cured by the maf and now the boost sensor seems to be affecting things.

The hesitation could also be down to sticking turbo vanes ot a clogged exhaust gas recirculation (EGR) valve too - have a look around that area and see if you can see any black goo seeping from the area - All linked together as the gas comes from the engine into the intercooler to be cooled then through the egr to the turbo (I think) and it's got particles in it which sticks and cakes the area in soot.

**Stunner** · 09-04-2009,01:18 AM

ive had an engine wash a few days back

but can you tell me where the EGR valve? i can check it 2mz. No changing the MAF ddnt cure anything at all. it still runs rough.

**benjie** · 09-04-2009,01:25 AM

Where in the UK are you as I'd also suggest you post in the VAG-COM section asking for help as a member could plug your car into that and scan the car for any fault codes that may be stored in the car's ECU.

Oh yeah, sorry. Under the bonnet, there's a silver circle shaped mushroom thing at the back on the left - that's the egr. It's not the easiest thing to take off and I'd suggest a haynes manual to do it with - if you don't have one, I can take a photo of & e-mail you the pages needed (I don't think it'll break copyright law as it's only 1 or 2 pages, less than 3% of the book anyway!) if you like?

I did it in the winter and as I was doing it the temperature dropped to -4.5 and my coke froze - my mate had to do up the allen key bolts as my fingers stopeed working properly!