Jump to content

Boost intermitent,


Joel93
 Share

Recommended Posts

Hi iv realised that after driving my impreza for 30 mins or so after a few hard accelerations the boost drops from 14psi to around 7psi. From what I've read this is limp mode but there is no CEL on, car has a cat back exhaust a panel filter and remap. Pulls really nice until boost drops off, after turning car on and off for 5 mins bost I'd back up to normal? Any ideas? Thanks 

Link to comment
Share on other sites


do you have an aftermarket boost controller fitted to vehicle if so my be worth dropping the max boost down a tad i had the same issue when it hit peak boost it shuts fuel off for a second and then runs normal.

Link to comment
Share on other sites

It's a 2004 wrx and I only had the car on the road a week, map was carried out about 8 years ago, there must be somthing bost related tripping it into low boost setting because its only happening after a few hard accelerations 

Link to comment
Share on other sites

Yes ,Lower octane fuel can cause it to lean off under boost,  which in turn might cause limp mode .

Have you got any proof it's been mapped ? 

As 14 psi (just under 1 bar) is a low boost target for a mapped car ,admittedly that could just be a inaccurate boost gauge .Most mapped cars will have the boost target upped to 1.2 to 1.5 bar pending on mods and engine condition .

If you dont have proof of a remap standard  boost target would be between 0.6 bar and 0.8 bar , you'd have to Google your model and year specific oe boost target. 

So if you're hitting 0.9 bar on a standard map boost target ,it could well be overboosting and that might cause it to go into limp mode .

Although you haven't got a cel light , I'd suggest to get the codes read while it's in possible limp mode . As it might log a minor fault on the ECU but not show a cel, due to it resetting when you restart the car .

Link to comment
Share on other sites

No it just has a td04, drove 180 miles  today and still boosting fine, parked car up and when to the beach.

Next drive I put my food down 1st gear boosting nice, 2nd gear boost to 14-15 psi, 3rd gear boost to 15psi then dropped back down to 7psi it then stayed like this until I turn the car off and back on. It seams to droop off as I hit 5000rpm ish. Is this over boost? After trialing out it can pull boost all day in 1st and 2nd but a hard pull in 3rd upsets it. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share






×
×
  • Create New...




Forums


News


Membership


  • Insurance
  • Unread Content
  • Support