Problems with performance

[valjo]

i have some problem with my aby. Some days cars performances are outstanding, but some days car simply wont go as good as it should. What should be wrong? i have some problems with fuel pump shutting of, but i checked maf connectors and the problems gone

thanks!

[Pisobiker]

What do you mean with "does not perform the way it should"?
Boost too low?
Boost kicks later in the rpm?
....whatever?


Marco

[valjo]

mybe boost is too low.
f.g; if car runs good it takes about 6s from 0-100
if car doesnt runs good it taks abut 7,5s from 0-100

should boost be too low?

thanks!

[Pisobiker]

If you don't have a boost gauge fitted, it's hard to tell if you have a low boost problem.
What about temperatures?
The reason I ask is just to make sure it's not a "heat soak" related problem.
With this hot climate (and Slovenia shouldn't be so different from Italy, I guess), it maight be possible you're just experiencing the annoing effects of too high intake temperatures that would iduce ECU to reduce boost and retard ignition advance.
The latter would also cause another effect: lower exhaust gas temps and energy, which means slower spooling up of turbine and boost coming in later in the RPM.
This kind of behaviour should of course start happen after some hard low to mid speed runs and on hot days.

Just some thoughts...

Marco

[valjo]

i think that temperature is reason, but today we have only 20c in Ljubljana Slovenija, so it cant be reason
i have some smal leak in smal hoses infront of intake mainfold, (guess to fuel system or. sth), but i havent located it yet...

[Pisobiker]

If you mean the hose coming out from front part of IM (looking at enginebay from front of car), it goes to the BOV (blow off valve) placed in the MAF-to-Turbo hose.

I would check both the hose and the BOV.

Marco

[valjo]

you confused me marco ops:

what is bov (blow of valve) and where it is? is it wgfv or bypass ventil?
in front of IM there is 2 hoses . one goes to ecu, oher goes to carbon canister or sth... i am realy confused with it ops:
look my threat: too much hoses.
sorry for my ignorance, i need to learn much more things about s2.
but it is my dream car and it is worth effort for it

[Pisobiker]

From front of IM ABY engine has only one hose coming out, and it goes to BOV (or bypass ventil, as you prefer).
So you probably mean the "BACK" of the IM (looking from front of enginebay) where is also placed Idle Pump and hoses for ECU, carbon canister, fuel pressure regulator and vacum accumulator come out.

If any of them are leaking, to make a test, I would suggest you use an air compressor with manometer (the one used for inflating tyres, for extence) fitting an adapter on it such as the ones used to inflate soccer balls. Put pressure over each of them (don't go over 1 bar) and hold. If pressure doesn't drop line is ok.

Marco

[valjo]

marco now we understand each other
it comes from back of IM yes
i did adapter and do boost test. i must have leak somewhere in those 2 hoses comes from back of IM. but as u know there is a very little room so i progress slow

thanks