alright lads need some advice on my fabia

 

i have been experiencing a lack of power in 1st and 2nd gears.  it is not completely gutless, however drives nowhere near as hard as it used to.  Sometimes it will be slow up until 3k and then suddenly theres a noticable kick in power until i run out of revs.  Really weird issue as i know that the gear i am in shouldnt affect the turbo in anyway at all really. some stuff ive tried is:

check for fault codes - all ok

cleaned maf sensor + checked wiring all ok

check map sensor wiring all ok

replaced o ring on turbo coupler

eradicated all boost leaks

confirmed vaccum present at turbo actuator (only through feel as i cant access vcds)

checked for stiffness in actuator rod - moves freely no tough spots

replaced vac box for n75 simplification

 

it is worth mentioning theres an audible hissing while on boost which i have narrowed down to the egr blanking plate. I cant get it to seal for the life of me, its the darkside kit and ive used exhaust paste and a new gasket to try and create a good seal, but nothing seems to work... im wondering the the plate itself may be bent or warped.  would this even cause such dramatic loss in power anyway?

 

any advice greatly appreciated cheers

It sounds like you have a vacuum leak somewhere, have you plugged the line to the deleted EGR valve?

That’s what I was thinking… I’ve examined all the vac lines, and since fitting the new n75 valve there is no need for the egr and asv vac lines

So you've deleted all the vacuum lines except the line from the pump to the N75 and the line from the N75 to the turbo actuator? What about the brake servo vacuum line?

So on the n75 the top line goes to the air box, one below goes to the turbo actuator and the one at the bottom has a T piece which joins the vacuum reservoir to the servo line.  This problem existed before I fitted the n75 anyway so I sort of ruled that out 😂 

1 minute ago, higgins57 said:

So on the n75 the top line goes to the air box, one below goes to the turbo actuator and the one at the bottom has a T piece which joins the vacuum reservoir to the servo line.  This problem existed before I fitted the n75 anyway so I sort of ruled that out 😂 

 

It ain't that then, boost leak?

There’s no obvious signs of a boost leak, no oil weeping from pipes and  For how slow it goes id expect some black smoke 😂 it’s doing my head in now 😐

Does it rev freely in neutral?

 

When you say you can't access vcds, do you mean you haven't got it, or it's not connecting, or it's not working properly?

 

Has it worked properly since you worked on the vac system?

 

I managed to cross a couple of vac lines on my 1.9 Octavia, it was ok to start with, but then suddenly would be well down on power. After a day it would barely run. I'm wondering if you might have run the wrong hose to the actuator, which is pretty much what I did. 

 

 

Bluetooth OBD2, Torque App on an Android phone or tablet, window mount and view - subject to correct data being reported - real time boost. The vacuum dial shows boost when turbo working, obviously tick-over on screen dump.

Try another MAF sensor. When they deteriorate they don't throe up a code until they fail completely. I have a lot of experience with mysterious loss of power, cured by replacing MAF. You can get a cheap Chinese copy on ebay and then splash some cash on a Bosch unit if it fixes the problem. Mine is a good one second hand for £24.00. (same symptoms)