RPMs eratically dropping
Newbie
Joined: Sep 2010
Posts: 91
Likes: 0
From: usa
mine didn't do it either at first otherwise i would have had the dealer fix it before i purchased the car. Might be one part of your issue. if you got stock DV put it back on and see if it help. Is you BOV venting into the engine bay?
Evolving Member
Joined: Jan 2011
Posts: 123
Likes: 0
From: Hyde Park, NY
Doubt it would be the blow off valve because I'm just running a stock evo9 bov and it happens to me from time to time
Ok, so I fixed my problem. It ended up being the Perrin intake that was on my car. I took it off and put on an Injen intake and intercooler pipes and my rpms don't drop anymore. Good luck to everyone else that has the same issue.
Open up Evoscan, select actuators and depending on version you are using either select SAS mode on early versions or Speed Adj, Screw mode on later versions.
Once the actuator is engaged the idle will either raise or fall, with what you describe would imagine the car will probably stall or come close to it. Turn the BISS screw until you achieve an idle of around 850 rpm with the actuator engaged. Once you have done this release the actuator, switch off ignition and reset the battery.
Once the actuator is engaged the idle will either raise or fall, with what you describe would imagine the car will probably stall or come close to it. Turn the BISS screw until you achieve an idle of around 850 rpm with the actuator engaged. Once you have done this release the actuator, switch off ignition and reset the battery.
Evolving Member
Joined: Jan 2011
Posts: 123
Likes: 0
From: Hyde Park, NY
I just figured out why my car is doing this today.
You have to listen closely but you might be doing the same thing
When lightly revving and feathering the throttle to creep forward, once you come off the gas to come to a stop again (say your moving in stop and go traffic), I can hear my BOV flutter lightly as the rpms fall below 1000 and almost stall the car.
I have a stock evo9 bov (uncrushed, recirculating), sitting on 24psi.
I'll be changing out that BOV shortly
You have to listen closely but you might be doing the same thing
When lightly revving and feathering the throttle to creep forward, once you come off the gas to come to a stop again (say your moving in stop and go traffic), I can hear my BOV flutter lightly as the rpms fall below 1000 and almost stall the car.
I have a stock evo9 bov (uncrushed, recirculating), sitting on 24psi.
I'll be changing out that BOV shortly
I'm having a simlar but opposite problem as your guys'. My idles will not come down below 1500 when idling, sometimes after driving they go all the way to 2k and slowly come down to 1500ish. It sounds like i need to adjust the so called BISS screw around the TB like Grayw suggested. I'm not sure why some of you didn't try his suggestion first, but oh well. i'll start with that.
ps. can anybody describe (or have pictures of) where this screw is at? is it on the IAC or the throttle body itself? i'm at work so i can't look in my bay till i get home, i'm sure it can't be that hard to find though.
ps. can anybody describe (or have pictures of) where this screw is at? is it on the IAC or the throttle body itself? i'm at work so i can't look in my bay till i get home, i'm sure it can't be that hard to find though.
well turns out my biss screw was set properly but my iac valve just had to be reset for some reason by disconnecting the ground from the battery after clicking on the actuator option on evoscan. weird.