Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

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.

Fuel Pressure Regulator on ej22 reconnected now idles strange

Featured Replies

Found A broken vacuum hose on gen2 liberty's ej22 it runs to the fuel pressure regulator so I reconnect it. Now when you first start the car the idle osilates between 250rmp and 1000rpm till it petters out after going up and down up to 2 or 3 times. I thought my car would run better with a functioning fuel pressure regulation system? Could this be the ecu relearning?

The swings between 250 and 1000 RPM are called "loping", and with engines that have electronic management, that's usually a sign of A/F mixture that's way off. It's possible that the ECU had adjusted parameters (long term fuel trim, for example) to the previous condition, and indeed it's readapting. It's also possible that the pressure regulator isn't functioning correctly, etc. You could try clearing the ECU's memory (disconnect the battery for about 30 minutes), and see if the problem resolves; it might, or could return.

  • Author

Yeh that makes sence as it was adding petrol for the vacuum leak and now that its gone does not know what to do with the 'extra' air its now seeing. How do you test a fuel pressure regulator?

  • Author

Alright I just disconnected my battery, Ill see in the morning if anything happens. Do I need to hold the pedal for the floor for two seconds and then at half throttle for two seconds when I turn on the car before starting?

  • Author

Just an update: resetting the ecu has fixed the idle issue thanks for the help OB99W.

Thanks for the feedback. I'm glad that resetting the ECU has apparently resolved the problem. :)

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

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.