massive jerk coming off the throttle

acssa · 07-07-2008, 01:35 PM

I have an 07 sti and I put APS CIA 65, 725 FMIC, BOV and HKS EVC6.

The car is now behaving strange serge, on steady 1/4 - 1/2 throttle...

BUT WAIT THERE IS MORE...

You get a single jerk of note coming of the throttle on a up hill full throttle.

Can anyone please help????

"From South Africa"

* Registered users of the site do not see these ads.

flycaster · 07-07-2008, 05:18 PM

That is throttle-off compressor surge - your BOV is too tight. Put a lighter spring in it - it should barely be closed at idle vacuum.

acssa · 07-08-2008, 12:55 PM

Quote:

Originally Posted by flycaster

That is throttle-off compressor surge - your BOV is too tight. Put a lighter spring in it - it should barely be closed at idle vacuum.

You do know your STUFF!!!

Two tuner shops could not fix it... even the one selling the bov.

Thanks alot

One last question

What would you choose, Cosworth or Brian Crower intermals?

flycaster · 07-08-2008, 01:54 PM

I answered that in your pm.

07-07-2008, 01:35 PM	#1
acssa Scooby Newbie Member#: 184023 Join Date: Jul 2008 Location: south Africa	massive jerk coming off the throttle I have an 07 sti and I put APS CIA 65, 725 FMIC, BOV and HKS EVC6. The car is now behaving strange serge, on steady 1/4 - 1/2 throttle... BUT WAIT THERE IS MORE... You get a single jerk of note coming of the throttle on a up hill full throttle. Can anyone please help???? "From South Africa" * Registered users of the site do not see these ads.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Moving the MAP sensor off the throttle body question	Hayaboosted	Factory 2.5L Turbo Powertrain	6	04-30-2010 12:21 PM
massive blowby coming from the crank case.	ownnij	Built Motor Discussion	8	04-24-2010 09:53 PM
Jerking coming off WOT	acid7711	Factory 2.0L Turbo Powertrain	6	09-21-2009 08:00 PM
massive jerk coming off the throttle	acssa	Engine Management & Tuning	4	07-14-2008 03:57 PM
Throttle Blip After Coming off the Throttle?	Shaved	Factory 2.5L Turbo Powertrain	18	04-05-2005 07:44 PM

07-07-2008, 05:18 PM	#2
flycaster Scooby Specialist Member#: 60142 Join Date: Apr 2004 Location: Bend, OR Vehicle: 2011 WRX Grey	That is throttle-off compressor surge - your BOV is too tight. Put a lighter spring in it - it should barely be closed at idle vacuum.

07-08-2008, 01:54 PM	#4
flycaster Scooby Specialist Member#: 60142 Join Date: Apr 2004 Location: Bend, OR Vehicle: 2011 WRX Grey	I answered that in your pm.