quick boost leak pointer

[karl210]

I know a lot of people are chasing boost leaks, ive been chasing one for a while now and i thought i tried everything, untill i reached down the back of my turbo this morning. The egt prope was loose tightened it up with a 17mm spanner and finally found that little ******! Ive been over the engine bay with a fine tooth comb and not even thought to check that so thought id share the tip.

 

[Greg-S3]

A valid pointer! Most people including myself forget about that and focus on boost pipes!

 

[James TQ]

silly question where about is it? can you see it or do you have to feel your way around?

 

[James TQ]

also have you noticed a big difference in the drive?

 

[Greg-S3]

When the turbo is cold to save burning yourself, reach down the back of the engine grab the turbo have a little feel around on the narrower body part and you should feel a 17mm 6 sided nut with a little rod and braided wire coming out!!

 

[karl210]

yeah the difference in the drive is great, the boost used to come in and give me a kick but tail off instantly with a hissing that was coming from behind the centre console. you can see it if you shine a torch down the back of the turbo, its a thin metal pipe that has a 90 degree bend in it and goes towards the passenger side. reach your hand down and behind the tip and give the pipe as it joins the turbo a wiggle, if you can turn it in the direction the prop shaft turns if you get me then its loose (probably the worst description ever)

 

[James TQ]

just had a quick look, couldnt make out where you were on about lol, ill try find a picture on here

 

[James TQ]

is the probe even on a ko3 lol?

 

[karl210]

any luck? ive had a look for pics on google but cant find anything decent. If you look down the back of the turbo you will see the actuator rod, just below this you will see a thin silver pipe coming straight out towards the rear of the car then bending 90 degrees to the right, best i can explain it im afraid, or try and follow the silver braided wire from the little black box under the inlet manifold.

 

[karl210]

is the probe even on a ko3 lol?

not sure, look underneath your inlet manifold and if you have a small black square box with an electrical connector on on end and braided wire coming out of the rear of it then yeah you do, if not then im guessing you dont have this

 

[James TQ]

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/109511-egt-sensor-location-03-s3-2.html ill have another look tomorrow, thanks guys

 

[James TQ]

dont think i have the sensor i can only see a probe on the downpipe

 

[aragorn]

EGT Sensor wouldnt cause a boost leak Its in the exhaust.


K03's dont have EGT sensors.

 

[karl210]

EGT Sensor wouldnt cause a boost leak Its in the exhaust.


K03's dont have EGT sensors.

thinking about it yeah your'e right, unless some of my exhaust gasses were leaking causing less gasses spinning the turbine or something? definately has helped a little bit though and some of the hissing has dissapeared

 

[aragorn]

It'll certainly have caused a hissing noise, theres typically more pressure in the exhaust manifold than in the inlet, but its not a boost leak

 

[<tuffty/>]

Its only facelift S3's (AMK/BAM) that have EGT probes.... A3's and pre facelift S3's (APY) don't have them...

<tuffty/>