Stall at decel with new turbo installed

[bpe121212]

Hey guys, I am in need of some help, Please!

I have recently added a Garrett BB 50 trim, Greddy RS BOV, Tial external wategate, and ETS FMIC and car now Stalls on deceleration and idles erratically. The AFR is extremely erratic at idle and seems to be jumping from 13.5/1 - 17.2/1. The car ran just fine (a little rich under load - 10.5/1) before New Turbo and FMIC install, even though I had already replaced the stock injectors with 750's and run with stock T-28 turbo and SMIC. I did a Boost leak test and found a leak through the throttle body tube going to the check valve of the evaporative emission canister. Is this OK? When I checked the evaporative Emission can while car was ruining I could feel air coming out of the exit port at the top marked AIR (nothing was connected to this port, it was vented to atmosphere). I also noticed a slight leek from the compressor housing where it meets the turbine plate (I guess this is expected since there is only machined aluminum meeting machined aluminum). Even though these leaks need to be adressed, the car ran just fine with these leaks when using the stock intercooler, turbo and BOV.



Thanks in advance for your help with this!

 

[mr2turbo]

is your blow off valve recirculated?

 

[bpe121212]

Yes.

 

[mr2turbo]

do you have an afc or anything?

 

[YiNYaNg]

What ems you running?

 

[bpe121212]

I am using ECU+ as my EMS

 

[andymoraitis]

Stalling on deceleration and poor idle are usually prime indicators of a vacuum leak, which you have at the EGR. Plug the line that's open to atmosphere and let us know the results. Also, you'll want to remove your compressor cover from the turbo and run a skim bead of grey RTV on the inside seal where it meets the backing plate and re-install it to to eliminate your boost leaks in that area.

Keep us posted,

Andy

 

[bpe121212]

Thanks !

I will seal the compressor cover as you suggested. Is it advisable to eliminate the evaporative emission and EGR system altogether or should I just plug the port on the Evaporative Emission can market AIR. I apologize if my questions seem somewhat rudimentary.

I really appreciate all your help!

 

[bpe121212]

I sealed Compressor against turbine plate and plugged EGR/Evaporative can tubes and car still stalls when decelerating, although Idle is much better. Boost leak test showed a small leak through the valve guides,at least that is what I think (can hear fluid slowly bubbling inside the engine) but the leak seams small and that was it. I am going to remove the Greddy-RS BOV and vacuum check for correct operation tomorrow. Is 15 lbs of vacuum about right?

I hope to run ~ 20lbs of boost once the car is baseline dyno tuned. My goal is to have the car running as best as I can before driving it to Northern VA for tune this Wednesday. The drive is ~ 240 miles.

Thanks!

Pres

 

[bpe121212]

I also found that the Idle Control Stepper motor was bad! This could certainly aggravate the situation.

Thanks again for all your help!

 

[bpe121212]

After replacing the Idle control Motor the idle improved, but the stalling continued. The new Greddy RS BOV was sticking closed and that was causing my stalling problem.

Success at last!!!