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.

Error Code 45 - Map Sensor. HELP!!??

Featured Replies

Hi All,

firstly please let me apologise if this is in the wrong section l, it's my first post.

Im having a problem that I cannot seem to cure, I keep getting a CEL every time I cold start the engine that goes out after about 5 minutes, it doesn't come on once the engine is warm, so I connected the read cables under the dash to find code 45, I changed the map sensor and the pressure exchange solenoid valve that sits below it and still the problem persists, if anyone can enlighten me as to why this is happening I would really appreciate it

Thanks Guys!

Jake


Hi n welcome , what model is it and has it been mapped or modded?

It could be a air leak between maf and map sensor . As this would make the ecu see a difference in the air measured between the air filter and inlet manifold.

Although I would expect that to show up more under boost than cold idle. It might be worth a visual check for perished vac lines and cracks in the intake and tmic y pipe .

  • Author

Hi, I appreciate your quick reply!!

its not mapped and currently the only "mods" it has is a silicone intake hose if you would call that a mod😂 And a HKS VTA BOV, other than that it has a standard intercooler and standard air box minus the resonator in the wing, I will check for vacuum leaks and would intercooler leaks cause the map sensor to see more air? 

thanks for your help!!

Jake

No problem ,bud .

A leak Anywhere between maf and where the inlet manifold connects to the heads , could show up a maf or map code .

It could be the new intake pipe allowing more air in than the stock one . As someone fitted a new intake pipe to their newage sti and although it ran fine, after 2 days they had a eml light come on at start up .

It's now been remapped and the light has not come back on but classics do tend to be a bit more forgiving when it comes to minor breathing mods .

Hope you suss it and keep us posted [emoji106]

  • Author

Hi Mate,

the problem seems to have moved from when the car is started to when I drive, seconds later it goes out, the error code is still 45 which says to me that maybe the wiring is faulty but as I say it only seems to come on when I hit a slight bump in the road, this problem is driving me mad!! I can't see any vacuum leaks around the tubes or anything so I think the issue could be wiring, and why it came on at start up could be because the wiring was not sitting right until I hit a bump in the road.

cheers for your help!

Jake


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.