Jump to content
SAU Community

Help, Idle Problems And Turbo Problems - Rb20det

R32-PSH77

By R32-PSH77,
in Engines & Forced Induction

 Share

Recommended Posts

R32-PSH77 Enthusiast

R32-PSH77

Posted
Posted

Hey guys.. i have recently upgraded the turbo on my Rb20det. to a T3/T4 using the RB25 exhuast housing thats been high flowed and a T4 Front housing and wheel ect.

Anyways i have bolted it onto the stock manifold and bought a new 3" mandrel exhuast from turbo back.. including highflow cat. Also bought a new bosch 023 800hp in tank fuel pump which i have all installed.

No my problem has been ever sinse i installed the turbo the car wont idle properly.. i know i need tog et the car tuned.. but money has become a bit of an issue at the moment.. so i drive the car quite conservatively and the boost is only a mere 7psi. but the idle not hunts up and down horrible.. and stall's quiet frequently... It seems to drive perfectly when its still on cold start.. like driven for the fist time of the day.. u put your foot on the clutch and the idle stays perfect.. but as soon as its warmed up.. as soo as you pull up and u put your foot on the clutch the idle drops to 0 and it stalls..

EXtermely imbarrasing.. i dont know what to look for.. i dont think its a simple case of turbing up the idle.. because if i give the throttle a little tap before it stalls.. it regains to around 500-700 rpm anmd hunt s a little.. but manages to idle a bit. so thats problem number one..

Also number two.. The new turbo seems to be surging.. it hasnt done it recently as i have tried boosting it at all.. but under heavy load.. eg going up a hill in a higher gear.. the compressor seems to fluctuates rapidly.. making a whoop whoop whoop sound.. it doesnt like being under laod at all.. its like the wastegate spring is too soft or something..

Anyways i got to goto work now.. if u need anymore information.. please let me know what u need to know.. and i'll anwser as best i can.. Thanks,.

blind_elk Grand Master

blind_elk

Posted
Posted

I reckon:

The problem at boost is compressor surge - you need a re-program of the ECU.

The idle problem is either an air leak (hose off somewhere) or a dirty AAC valve.

R32-PSH77 Enthusiast

R32-PSH77

Posted
  • Author
Posted

at the moment im using a Amto BOV.. but i never had this idel problem before i setup the new turbo.. i used to have the return pip[e from the standard setup blocked of and im currently running a Type 3 turbosmart bov.. ive tried it wound up tight and mid range.. both have no effect on idle.. its really ghey.. i sorta have to bleep the throttle before coming to a complete stop.. to stop it from stalling.. and feather the throttle in conjunction with the handbreak to pull up the car without stalling... i don't see how having a diffrent turbo would effect the intake of air during idle.. its barely spooling at idle is that right?? could it be a shagged AFM?

Starionturbo Mentor

Starionturbo

Posted
Posted

My ceffy has no blow off valve and this problem has come about all of a sudden.

Last service about 2 weeks ago, I noticed one of the lines to the charcoal cannister had perished and pretty much come offso I put a new vaccum hose on.

I thought this would solve my problem.

Since then its the same thing, come to the lights the idle hunts, it doesnt stall but it gets DAMMN close.

Ive checked over the vac lines plenty of times. The air flow meter has been cleaned, oxy sensor replaced.

I dont know what else? Im getting horrendous Fuel economy as well - like insanely bad.

  • 11 months later...
Hydroxinol Enthusiast

Hydroxinol

Posted
Posted (edited)
No my problem has been ever sinse i installed the turbo the car wont idle properly.. i know i need tog et the car tuned.. but money has become a bit of an issue at the moment.. so i drive the car quite conservatively and the boost is only a mere 7psi. but the idle not hunts up and down horrible.. and stall's quiet frequently... It seems to drive perfectly when its still on cold start.. like driven for the fist time of the day.. u put your foot on the clutch and the idle stays perfect.. but as soon as its warmed up.. as soo as you pull up and u put your foot on the clutch the idle drops to 0 and it stalls..

Sorry to resurrect an old thread but it looks like this never got resolved.

I have the EXACT same problem. It started ever since I installed an RB25Turbo on my RB20DET with a stock BOV. At first I thought it was due to an air leak, but I fixed it with no success. I have also recently cleaned my AFM and AAC Valve. I was having idle hunting issues before I installed the turbo, and this was solved by cleaning the AAC Valve. Is it possible that it or something else could have become clogged up again while running the new turbo in? I have also tried reseting my ECU with no luck. I notice at idle that the vacuum reading on my boost guage seems to fluctuate slightly, don't know if this is the problem, or a symptom.

Any ideas?

Edited by Hydroxinol
Hydroxinol Enthusiast

Hydroxinol

Posted
Posted

I solved my Idle problem.

Symptoms:

Car idle slowly drops down to near stalling and then raises back up to normal idle momentarily. This only occurs when stationary at idle with car at operating temperature. Tapping the accelerator will also send the idle on a skydive down and it will studder until it slowly raises back to normal.

Cause:

Faulty O2 Sensor. The car idles normal at cold start because the ECU ignores the O2 Sensor until it is at operating temperature. Once the O2 Sensor is at operating temperature, the ECU will begin to read the voltage from it. If your O2 Sensor is faulty, it will not be able to give the ECU a quick, accurate result, and will result in poor idle as the ECU acts on this false reading.

Solution:

Check O2 Sensor with a multimeter to confirm if it is faulty/dead. The following site contains an FAQ on how to do this: O2 Sensor FAQ

On my multimeter I noticed that it did not go under 0.45V, and when revved at 2,000rpm it stayed at a constant voltage. It shouldnt do this, a functional O2 Sensor should fluctuate rapidly.

Hope this helps.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • sausagepianist
      V36 2008 Coupe Wiring Differences with Android Screen

      By sausagepianist · Posted

      Right, here's a video of the basic operation at least.  This is what you can expect day to day when you turn the car on and it boots from standby.  The only thing from a media point of view I haven't gotten working is for it to autoplay plexamp when it turns on from standby (it works from cold boot) but that's more of a plexamp problem as it will autoplay other music players.  Also attached is my one stray cable.  It's part of the screen's wiring adapters but there's just nowhere for it to go in my car.  I've just now done a bit of research and found a matching port on a 2010-2014 head unit with BOSE.  Mine has no BOSE so that's that case pretty much closed I think.  Plugging in the Infiniti AC panel basically did nothing for me, so that's a dead end as well.  Next port of call is to mess with this CANBUS module and see what I can find from it.  I found this resource containing the DBC files for a 2010+ G37 : https://github.com/icecube45/Dash_InfinitiG37/blob/master/InfinitiG37.dbc I'll now have something to go from when I try to extract my CANBUS data so I can see if the HVAC Mode, Fan Speed, Temperature, etc. match and also the gear shifter position.  It's a pretty big assumption that it's just mismatched CAN signals but considering all the devices in the CAN network are talking to each other (AC can be fully adjusted just with no info on screen) it might be a safe one.  I will report back WhatsApp Video 2025-02-26 at 12.49.10.mp4
    • sausagepianist
      V36 2008 Coupe Wiring Differences with Android Screen

      By sausagepianist · Posted

      Thanks for that Paul.  Do you think if I posted a picture you'd be able to remember where it went? 
    • sausagepianist
      V36 2008 Coupe Wiring Differences with Android Screen

      By sausagepianist · Posted

      Sorry Duncan, I didn't get a notification for the replies.  Thanks for responding!  It's a full Android device, but does allow you to use CarPlay/AA as well.  This is the one I bought from NaviRS on AliExpress: https://www.aliexpress.com/item/1005006368602668.html?spm=a2g0o.order_list.order_list_main.111.59aa1802JDzQ0E - the 2K 8G-256G CAM variant but it seems to have gone up by £170 since I bought it!  My purchase was ￡307.14.   It's not the fastest thing in the world but performs perfectly adequately.  It stays on standby unless I disconnect the battery and let it power down, then it's just a fairly standard Android bootup time from cold.  The DSP Equaliser is very nice and made the standard stereo system sound pretty decent compared to the stock screen.  Perhaps I can take a video of it when I get a sec. It *allegedly* supports the reverse camera, but I'm yet to get that working.  It has options for reverse cam (a camera unit can be bought separately) or 360 cameras (also bought separately).  To be fair it doesn't seem to detect that the shifter was put into reverse but I'm working on a theory about this as well.  At the moment I'm going without which is a bit annoying considering the car is an absolute canal barge but so far I haven't caused any damage I'll grab a picture of the wire I'm missing later today when I can get outside.  My theory, by the by, is that not only is the head unit different, but the CANBUS network has different signals for the different years.  I think this because I have a spare AC panel from a newer Infiniti G37 (as opposed to my Nissan panel) which wouldn't control anything except the volume when I had it wired up with the stock system.  I'm going to throw it back in and see if the screen will respond to it.  I've just ordered an arduino CANBUS module so I can have a look at the signals going around the car and see if I can spot anything.  I'm thinking if I can work out what it's expecting vs what it's getting I might be able to translate and relay the signal back but so far just a theory anyway. I also found this on my travels, so far the only one that specifically matches my car: https://www.aliexpress.com/item/1005002822934280.html?spm=a2g0s.imconversation.0.0.33433e5fgttovi If you look at the picture of the before, it has the card reader slot, and the picture of the head unit is exactly the same as the one pictured in my original post.  I asked if they sell the cables separately but sadly they won't.  I didn't want to just buy this one because it's a super old Android version and only dual core - likely slow as hell. 
    • sonicii
      V35 Overheat + Coolant Boil & Overflow + Engine not Starting

      By sonicii · Posted

      As above, you did refill the coolant and burp the system before running it again didn't you?
    • GTSBoy
      UniClutch

      By GTSBoy · Posted

      To be fair - you see the same thing for every clutch. There's always someone making an installation error.
×
×
  • Create New...