Jump to content
SAU Community

Rough/erratic Idle

cainer33

By cainer33,
in General Maintenance

 Share

Recommended Posts

cainer33 Explorer

cainer33

Posted
Posted

So yeah, I have put some JJR's on and they fixed my misfire under boost, car runs great now.

But I have a rough idle, sometimes when I stop im doing 800rpm other times its 1100rpm.

I have cleaned out the AAC valve and the idle no longer hunts but I did notice something on my apexi turbo timer.

When the car was cold and I had it selected to O2, it was slowly counting down the voltage as the car warmed up, the idle reduced accordingly.

When I took it for a drive it stayed locked on 4.99volts, it didn't change at all even when I stopped.

So I am wondering, would an O2 sensor thats probably on its last legs and working intermittantly (which is what I think is happening) cause an idle that goes from normal range, but burbly, to 1100rpm and random times.

The idle isn't perfect either, bit of a burble here and there, up the rev range though, no problems at all.

Link to comment
https://www.sau.com.au/forums/topic/279762-rougherratic-idle/
Share on other sites
Muff Rising Star

Muff

Posted
Posted

could be.... have you got a votage stabiliser????

does your car idle better when it cold or hot?????

when the car is cold your o2 sensor is in what callled an open loop circut. therefore not really doing anything untill its warmed up, when it goes into a closed loop..... my sugestion is to put a voltmeter on it and test it out... or even take it out and have alook...... if it looks f*ked ... go and get another 1 from bosh......$75

GL

lukebaldan Collaborator

lukebaldan

Posted
Posted (edited)

Are you sure the O2 voltage is being reported correctly? Perhaps the turbo timer was not connected to the o2 sensor output? It should range from 0-1v (Sweeping back and worth when you hold revs constant above 1.5k)

A completely dead sensor (open circuit) will read ~0.3v (Reference voltage the car spits out).

It may spit out something close to constant 0 or 1v otherwise if something else is wrong with it.

If this was the case, your car will let you know. I have a 34 and if you unplug the o2 sensor, the check engine light comes on within 5-10 minutes.

In any case, the o2 sensor shouldn't cause problems at idle (I think the car runs in open loop anyways at idle).

Not sure about the 33's but the VCT solenoid can cause erratic idle if it's defective (What i have observed anyway by manually turning on/off the solenoid at idle with a consult cable).

Edited by lukebaldan

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

    • mr.torquesplit
      T56 In Gtr

      By mr.torquesplit · Posted

      looking forward to your t56 swap man its a game changer if it works! 
    • Kinkstaah
      MLR's Bogan cruise ship

      By Kinkstaah · Posted

      So, when are you trying the new GR86 or BRZ?
    • The Bogan
      MLR's Bogan cruise ship

      By The Bogan · Posted

      Uncle Duncan Yeap, FI Interchiller  Works well, normal IAT's cruising with the WTA only went from 50°c+ to 25-30°c with the interchiller  Before, when on it hard, the IAT would see 80-90°c, now, the highest has been was around 38°c IIRC IAT is measured under the blower hat I recommend it for the street or strip where your only on it hard for 10 or so seconds, but it wouldn't be efficient for sustained track use as it would heat soak from the AC turning off or whatever it does during WOT to protect the compressor It really needs the AC running for it to not heat soak and keep the WTA coolant chilled My WTA coolant temps when just cruising is around 2°c
    • Duncan
      MLR's Bogan cruise ship

      By Duncan · Posted

      Hey Mark...sorry to interrupt your career change to hair dressing... but...did you ever fit the interchiller to the commodore, and if so how was it? And, who made it?
    • The Bogan
      MLR's Bogan cruise ship

      By The Bogan · Posted

      I've been pondering this, I really enjoy the convertible thing, for me, it's like riding a motorbike, without all the issue of riding a motorbike, mainly, my old sore arthritic joints getting beaten up, and, being able to do it in shorts and a T-shirt and not needing a helmet and all the other gear required, especially like wearing jackets and pants in the summer, or needing 6 layers of cloths in the winter, or not having wet weather gear handy when your 100km away from home on the bike when it decides to start raining As for the hard top and its Coupe look, whilst I do lose all that open top feeling that I really enjoy, from my experience with the NB with a detachable hard top, the cabin is a much nicer place to be, the difference in noise for one, a hard top quietens down the interior, alot, with the soft top up or down it's pretty noisy, which, after 5 or so hours, can get tiring But, as you stated, the detachable hard top totally changes the look of the car, in a really good way, and for me, the look of a detachable hard top is so much better than the PRHT which looks more like a after thought with its weird bulbous rear roof line For me, the minimal effort of putting in on, or storing it after removing it, is well worth the time and effort for the look alone And yes, I'm sure the next owner will be grateful for it as well.......  
×
×
  • Create New...