A3 1.4tfsi engine air leak

[Dasherz]

Hi all,

‘I’m new here.

Ive got a 2015 1.4tfsi A3. Only done 22000 miles, has run sweet till now. I’m an ex mechanic so I decided to service the car myself and it was a piece of cake; just changed the oil and air filter. Anyway, the car ran fine for a day or so then the other day the yellow EPC light came up on the dash and there is lack of power but runs well, no misfires. I read the codes and it came up with P2279 system air leak. I’d assumed id dislodged an air pipe somewhere but nothing, all looks great. I can’t for the life of me see any obvious issues. When I started the engine after the oil change I did run the engine for a bit without the oil filler cap on, I was wondering if that effected anything maybe? Any ideas anyone?

Much appreciated

 

[Magnet]

Hello Ashley,

On the basis of simple things first and the limited dismantling you must have done :- 

What make air filter did you use? 

Kind regards,

Gareth. 

[Dasherz]

Hi 

Thanks for replying.

I simply replaced the old air filter with a Bosch replacement that looked identical to the old Audi supplied filter. There are two large clips connected to the filter housing that I unclipped and then removed housing, replaced filter and reassembled. I removed the cover on the bottom of the car to drop oil and replaced after. 

[Magnet]

Hello Ashley,

I’ve used Bosch air filters without issue and the fitting arrangement sounds similar to our much earlier A3, so I would say it’s fair to discount any issue there. Associated pipework? ...but as you say that seems to be OK, so a bit of a mystery. 

One possible trick would be to carefully spray some WD40 on the associated air intake pipes while someone holds the revs. steady at around 2000 rpm and see if you get any tell tale smoke from the exhaust - pointing to an unseen entry point for air.

Kind regards,

Gareth.

 

[Dasherz]

Hi,

I was gonna try the propane method on the joints though I’m not optimistic as nothing was disturbed, I’ll give it a go. I’ll probably remove the filter and check that it’s all good. 
 

thanks 

[Magnet]

Personally, I certainly wouldn’t use propane - far too combustible!! 

What’s wrong with far less combustible and safer WD40? 

[Dasherz]

The results with propane will be quicker as it’s a gas not a liquid and I won’t get wd40 over everything. The engine tone will change. Do it in a well ventilated area with a fire extinguisher at hand. At least if it ignites it will be a quick flash, no harm done, we’re only talking about tiny amounts of gas here.