Do Not Sell My Personal Information Jump to content
View in the app

A better way to browse. Learn more.

Subaru Owners Club UK | Subaru Forums

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Slightly erratic idle

Featured Replies


  • Replies 53
  • Views 7.9k
  • Created
  • Last Reply

Top Posters In This Topic

Most Popular Posts

  • I also had this problem. is the MAF sensor. carefully reading it wrong sends incorrect information to the ECU. you could have a rich or lean fuel mixture. in 10 years I have changed maf sensor 7

  • Harryburgundy
    Harryburgundy

    Cool...let us know when they arrive and what you get. No time to look at anything this week...off for a lovely long weekend in Devon tomorrow :-)

  • No not yet anyway I might have a PDF workshop manual for you car and it will be free :D 

  • Author

Okay...finally got around to checking for ECU codes. Nothing. Steady long flashes

  • 1 month later...
  • Author

Idle problem not getting any better...someone has suggested that the IACV could be gummed up and on YouTube there is a vid of someone cleaning it using Subaru Upper Engine Cleaner. 

Does anyone have any experience of this?

Carl

  • 1 month later...
  • Author

Not much of an update. I have 'cleaned' the engine using Forte engine cleaner and Forte injector cleaner. The result? Much improved acceleration and general smoothness but the idle prob still present. Waiting for some MAF cleaner to arrive then, with the Forte intake cleaner I already have, will give all the inlet stuff a good clean.

I know rough idles are a pain to track down I've done it twice myself, once as I said Maf and 2nd was a split hose on another car. Took me ages finding the hose with the split :( 


  • Author

Aye...pain in the butt. Cleaning air intake and maf today. Smoke me a kipper

Where did you purchase the cleaners from good sir ?

  • Author

Both the Forte and CRC stuff from g'ole EBay. Have cleaned both now (throttle body and butterfly valve were a bit dirty) and will test drive later. Wanted to clean tcv too but think I need a new seal bag before dismantling. Could be wrong, as usual.

  • Author

Meh...definate improvement in acceleration/pick-up but bl**ding idle still being silly.

Mmm...plugs, leads and coil next. !Removed!

Did you just clean the MAF I know that doesn't always work. Well never worked for me on 2 separate mafs, wasn't until I bought a third one it sorted it :( 

 

But if the plugs need or are due to be changed that would be my next stop before anything :) 


  • Author

Hi Gambit

Yup, just cleaned the MAF and throttle body. As you say, plugs etc next although in my little head I don't know why that would be it (and several people have told me it could be that). I thought bad plugs or shorting coil would result in rough, spluttering idle

  • Author

Oh...to explain. My idle isn't rough or pulsing/hunting...it just, on occasion, runs at 1200 or 1500 or 2000! Like I had my foot on the pedal.

So it would increase the revs not drop/stall ?

  • Author

That's correct. Normally it will sit steady at circa 600 but occasionally it doesn't drop down and stays at 1200-1400, sometimes more

Oh right so could have been looking in the wrong places still could be a few things :( 

 

Throttle Position Sensor 

Lambda Sensor (< Would be my main guess )


No not yet anyway I might have a PDF workshop manual for you car and it will be free :D 

  • Author

Not working in my phone, will try at work later. Thanks :-)

I clicked it gives me an option to download it but it's my link let me know :) will try do it again  if it doesn't work :D 

I will have a look might need winrar to unpack it 

Create an account or sign in to comment


Background Picker
Customize Layout

Account

Navigation

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.