Turbo lag
 

hey all


I have an 07 with the only thing I have changed being adding a K&N filter. In my normal city driving, I seem to be getting more turbo lag than I think I should. Any advise?

Z

clean ur filter if u havent yet, (check that screen too) run a bottle of fuel injector cleaner and see if the problem happens the next time you fill up because u could have just gotten less then good gas

Get it chipped!

what is your definition of turbo lag? The car does have a small lag, initially depending on what gear you are in. Maybe try to describe the symptoms a tad more.

p.s. if you want to get chipped let me know :P

turbo lag happens with the pedal is initially pressed down around 2 thoudsand or lower rpms and doesn;t have enough exhaust pressure to spin the turbo fast enough to build boost...at around 28-29 hundred you create enough pressure to spin the spool fast enough to create a pressure which gives you the boost....every turbo has it,but its not somehting that increases with time

it's an annoying characteristic with single turbo engines. if you want to spend some coin, do this:
1. milltek high flow cat and cat back
2. chip w/ new diverter valve
3. AWE front mount intercooler (just for power gains)

mod 1 and 2 will reduce the lag. mod 1+2 will help even more.

PCV Valve
 

was blown out, that was the root of the problem, the dealer repl and viola back to normal. I think I am gonna start small and get a HFC and it chipped as I do crave a bit more oomph.

Z

When I got my 2007 A4 - I was sincerely worried because I found tip in throttle response to be...difficult due to the "lag".

For another unrelated transmission issue, they flashed my TCM to level 50 (From 35). I can actually feel the software difference.

It now sort of "bleeds" off the power as the car revs slowly in city traffic, almost no neck jerk now....hell, the only way I know it's a turbo is when i'm on the highway...and go VROOM.

You are describing boost threshold not lag.

http://en.wikipedia.org/wiki/Turbocharger


Turbos do tend to decrease over time as the the parts wear, EBC's even have a feature that allow you to help over come this issue. If a N75 valve is being used to control boost you could notice a drop in power since the ecu does not adjust for a drop in boost pressure, the problem is that the N75 signal to open is set and isn't based on boost that is actually being made like a EBC does.

Turbo Lag


A pair of turbochargers mounted to an Inline 6 engine (2JZ-GTE from a MkIV Toyota Supra) in a dragster.
The time required to bring the turbo up to a speed where it can function effectively is called turbo lag. This is noticed as a hesitation in throttle response when coming off idle. This is symptomatic of the time taken for the exhaust system driving the turbine to come to high pressure and for the turbine rotor to overcome its rotational inertia and reach the speed necessary to supply boost pressure.

pulled off wiki sounds just like what i tried to describe