[MarkMac-RS3]

Morning lads.

Right, I know what this fault code mean leak in air intake system. I have two assumptions here, I’m guessing it must be downstream of the MAP so will either between the plenum and intake manifold or manifold and block. My other assumption is that this will make the car run rich as it now pops on downshift and slowing down also there will be charge air being squeezed out any leak path in turn making the car run rich as there is less metred air entering the cylinders. If anyone could shed some light on if I’m right or wrong. This is all for my own information, I just like to know how things operate.

[JayRS3]

Have you tinkered with anything recently that could have caused a vacuum leak?

Have you tried opening the oil cap at idle to see if there’s any change in engine noise/ vacuum present? This will prove the breather valve.

Any hissing under the bonnet to maybe pin point a leak?

Was there any other codes other than P2279? When it resets does it return instantly?

Check your runner flap arm left side of block.

[MarkMac-RS3]

Have you tinkered with anything recently that could have caused a vacuum leak?

Have you tried opening the oil cap at idle to see if there’s any change in engine noise/ vacuum present? This will prove the breather valve.

Any hissing under the bonnet to maybe pin point a leak?

Was there any other codes other than P2279? When it resets does it return instantly?

Check your runner flap arm left side of block.

Just had the timing chain etc done Jay.

No other fault codes at all.

Tried the cap yesterday and idles smooth regardles, didn’t stick my hand over but it did sound as if it’s sucking air.

Runner flap arm is fine and sitting in the normal position. Was moving when I got the missus to rev the car as well.

EML was out for a good 20-30 miles then it came back on mate. The car doesn’t run any worse when’s it’s on.

I can’t hear any hissing but it does sound like there is a lot more air being sucked in via the air box. Maybe just hearing that now because my DMF is not chattering anymore 😂

I’m putting it in to get investigated so will find out for sure.

Edited by MarkMac-RS3, 08 April 2018 - 11:47 AM.

[JayRS3]

Just had the timing chain etc done Jay.

No other fault codes at all.

Tried the cap yesterday and idles smooth regardles, didn’t stick my hand over but it did sound as if it’s sucking air.

Runner flap arm is fine and sitting in the normal position. Was moving when I got the missus to rev the car as well.

EML was out for a good 20-30 miles then it came back on mate. The car doesn’t run any worse when’s it’s on.

I can’t hear any hissing but it does sound like there is a lot more air being sucked in via the air box. Maybe just hearing that now because my DMF is not chattering anymore

I’m putting it in to get investigated so will find out for sure.

It’s unmetered air entering at some point. May be worth checking around your throttle body area etc. Obviously with your last job recently a lot of components/hoses would have been disconnected and may not have been put on all the way and now it’s just come away ever so slightly causing a leak. Could be a headache to find from the previous work carried out. Probably even harder to find if the car isn’t affected too as it must be only a small quantity to enable the error code

Edited by JayRS3, 08 April 2018 - 11:57 AM.

[MarkMac-RS3]

Turns out it was the breather, new rocker cover fitted and it’s running without any lights again.

[JayRS3]

Was it from a leak test mate?

[MarkMac-RS3]

Was it from a leak test mate?

I think so, he said he carried out a boost test as well as other things. Found a small leak between the plenum and intake manifold. Also found the diaphragm was gone in the breather.

Edited by MarkMac-RS3, 12 April 2018 - 05:08 PM.