(Y) Tried searching to no avail.
My car has always done this but I'm just trying to get to the bottom of [WHY].
Whenever I do a quick high rev (car is parked, in neutral) my idle has the tendency to rev up and quickly dip below 200 and then back up to 850rpms and stabilize.
No issues if I do a slow and methodical throttle rev (gradual up and down).
Additionaly, I have to down-shift when slowing down.
It will certainly shut off when I throw the clutch in and slow down quickly from high speeds.
Unless I blip the throttle, down-shift, and gradually slow down.
No issues cold starting.
Car idles clean...it just doesn't return to 850rpms smoothly
Car has a valid tune
Did a boost leak test recently when I recirc'd my BOVs and no issues to report
Here's what I think may be the problem(s):
- IACV is now allowing free flow of air when the throttle is closed
- ECU is not in control of the IACV
What else can I check to diagnose this issue?
Thanks in advance.
#########EngineModsBelow##########
==Engine Stage II+ Longblock==
VG30DETT
* Wiseco Forged Pistons/Rings
*New Nissan Rod and main bearings
*New Eagle H-Beam Rods/ARP Rod Bolts
*New ARP Main Studs
*All new freeze plugs
*Competition Valve job
JWT Cams #400
JWT Valve Springs
Tomei Intake cam sprockets
New Hydraulic lifters
Water pump
*New Valve Seals, stem height set
*Cam Journals Polished
*Complete Gasket Set
*Complete Timing Set
OS Giken RC3 “Triple” clutch
ATI Super Street Damper Crank pulley
UR OVERdrive H2O pulley
UR ALT pulley
UR 4-rib pully for N/A P/S pump
==Fuel Supply==
300Degree Rail
Sard 850cc injectors
AshSpecZ Dual Fuel Pump Controller
Dual Walbro 255lp -6AN bulkhead modified stock pump assembly
*Earl Braided hose (-8AN Supply & -6AN Return) long haul/Russell Classic under hood
==Forced Induction==
Garrett GT2860RS "Disco Potato" (Swain Coated)
AMS Ported Max Flow manifolds (Swain Coated)
AMS SS 3.0 DP (Swain Coated)
AMS 3.0-2.5 TPs w/ WB02 bungs
HKS High Power Cat back
JWT Dual Pop charger
CZP 2.5 Intercooler Kit
Dual HKS SSQV BOV
SELIN Dual MAF kit
Z1 SMICs w/ AshSpecZ 2.5"ID mod inlet/outlet
==Cooling==
AshSpecZ Double-Pass radiator & Spal E-fan
AshSpecZ X-Coolant tank
11 Row Oil cooler -10AN fiitings
Accusump Oil Accumulator w/ 35-40psi EPC -10AN
MOCAL sandwich plate -10AN
==Electronics==
SpecialityZ chip
Blitz SBC I-Color Boost controller
HKS Twin Power Ignition Amplifier
Autometer Digital Phantum WB02 A/R gauge(s)
Autometer Digital Phantum II FP gauge
Autometer Digital Phantum II V+/- gauge
Autometer Digital Phantum II 30PSI Boost/VAC gauge
AEM Water-meth pump
AEM Water-meth pump safety monitor w/ gauge
AEM X-Wifi
Optima Red Top
AutoPage C/3 915
==Stance==
PowerTrix FUCAS/RUCAS
PowerTrix ADJUSTABLE FRONT TENSION RODS
PowerTrix ADJUSTABLE REAR TRACTION RODS
AMS Max HICAS Delete
KYB AGX Pro Kit w/ Eibach Lowering Springs
*PowerTrix Sport Street Coilovers (to be installed later)
StopTech BBK 14.1 2pc Sloted Rotors (F)
StopTech SS lines (F/R)
StopTech Sloted Rotors (R)
Varrstoen ES 2.2.1 19"
Nitto ENVO F235/35/19 R265/30/19
Energy Suspension Hyper-Flex rear bushing kit + spindle bushings
==custom modifications==
fuel pump assembly, all AN bulk heads
-stock fuel lines removal
trunk mount battery
1/0 gauge starter cable
HICAS complete removal...all lines & hardware etc
==Wish list winter build 2011-2012==
AEM EMS Series 2
AutoPage C/3 1100
Fuel chiller
WinFactory top-feed rail w/ ID 1200cc
WinFactory diffuser
external paint job
N/A Subframe
N/A rear diff
N/A Solid Driveshaft
DIY roll bar
StopTech rear BBK
