Notices
Drivetrain Gearbox, Diffs & Driveshafts etc

Overboost??

Thread Tools
 
Search this Thread
 
Old Sep 23, 2002 | 02:45 PM
  #1  
Simmo2's Avatar
Simmo2
Thread Starter
Scooby Regular
 
Joined: Aug 2002
Posts: 279
Likes: 0
Question

Hi All
Now i know this as been covered before but i just want to check.

Now that the mornings are slightly colder when accelerating hard from 3rd through 4th, 5th i get the brick wall syndrome at around 5,000 rpm. But in the afternoon not. Is this overboost or just a car that likes a lie in, in the mornings.
MY95 uk 5 door turbo.

Had the car 2 months.Tottaly standard.
recently started using optimax
Dealer service 3 weeks after purchase.

Many Thanks

Pete
Reply
Old Sep 23, 2002 | 06:50 PM
  #2  
Simmo2's Avatar
Simmo2
Thread Starter
Scooby Regular
 
Joined: Aug 2002
Posts: 279
Likes: 0
Post

bttt
Reply
Old Sep 23, 2002 | 08:07 PM
  #3  
Moles Dad's Avatar
Moles Dad
Scooby Regular
 
Joined: Feb 2002
Posts: 1,446
Likes: 0
Post

Probably

Are you sure you dont have a de-cat zorst ?
Reply
Old Sep 23, 2002 | 08:57 PM
  #4  
Simmo2's Avatar
Simmo2
Thread Starter
Scooby Regular
 
Joined: Aug 2002
Posts: 279
Likes: 0
Post

Hi Moles Dad

Nearly 100% sure as this wa owned previously 1 owner who hhad everything done by subaru. No other parts on the car that were not subaru, it's as if the car was owned by Mrs Subaru.

Its a weird sensation though when you get it to do that.
If you just lift off a touch the car just takes off no probs.

Pete
Reply
Old Sep 23, 2002 | 10:30 PM
  #5  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Question

I have the same problem too, just had 3 experiences of brick wall hitting without hitting a wall

The first occurred in 1st, the other 2 in 3rd giving it some throttle too. I've just noticed that the battery light flicks up when it dies then remove throttle, apply throttle and away she goes, this is weird. Anybody got any clue's.

Thanks
Reply
Old Sep 24, 2002 | 06:59 AM
  #6  
dowser's Avatar
dowser
Scooby Senior
20 Year Member
 
Joined: Oct 2000
Posts: 3,105
Likes: 0
From: Zurich, Switzerland
Post

Check oil level and the boost solenoid/pipework for oil contamination...clean everything out - too much oil leads to this problem, so if it's too high now get some drained before you clean.

Richard
Reply
Old Sep 24, 2002 | 07:57 AM
  #7  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Thumbs up

Thx Richard, will investigate later.

Boost solenoid is on strut pillar !! (is this correct)
Reply
Old Sep 24, 2002 | 08:08 AM
  #8  
P20SPD's Avatar
P20SPD
Drag it!
iTrader: (1)
 
Joined: Jun 2002
Posts: 9,866
Likes: 0
From: Flame grilled Wagon anyone?
Post

yeah drivers side.

hade shed loads of overboost this morning, mainly in 4th
Reply
Old Sep 24, 2002 | 08:28 AM
  #9  
Simmo2's Avatar
Simmo2
Thread Starter
Scooby Regular
 
Joined: Aug 2002
Posts: 279
Likes: 0
Post

Tell me about it. left home for work at 7am coming down M4 & M5 it was awfull but once you learn to just take of the gas a touch then she flies.
Reply
Old Sep 24, 2002 | 09:00 AM
  #10  
P20SPD's Avatar
P20SPD
Drag it!
iTrader: (1)
 
Joined: Jun 2002
Posts: 9,866
Likes: 0
From: Flame grilled Wagon anyone?
Post

Correct! was difficult playing with a **** head in a tvr tuscan when you are getting overboost and the red light is on for fuel
Reply
Old Sep 24, 2002 | 09:02 AM
  #11  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Lightbulb

But I want to keep the right foot down, don't want to keep lifing off. Its bloody dangerous anyhow cutting out, could be crucial as in roundabouts or traffic lights.

I was told last night that a Fuel Cut Defender (FCD) is required to remove this. Can anyone shed some light on this item

[Edited by caz1562 - 9/24/2002 9:18:25 AM]
Reply
Old Sep 24, 2002 | 12:01 PM
  #12  
dowser's Avatar
dowser
Scooby Senior
20 Year Member
 
Joined: Oct 2000
Posts: 3,105
Likes: 0
From: Zurich, Switzerland
Post

Fuel cut defender will modify or remove fuel cut - which is what overboost is really (too much boost, so ecu cuts fuel).

If you're getting overboost since the colder weather I wouldn't be looking at an FCD....fix the 'boost too high' issue.

Richard
Reply
Old Sep 24, 2002 | 12:40 PM
  #13  
Simmo2's Avatar
Simmo2
Thread Starter
Scooby Regular
 
Joined: Aug 2002
Posts: 279
Likes: 0
Post

when i first started getting this my dealer said "know what it is bring it in when you can bear no more and when its colder"

well i think im there now!!
Reply
Old Sep 24, 2002 | 02:27 PM
  #14  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Post

Was talking to the guy at the garage earlier and he suggested I adjust the wastegate actuator, anyone ever adjusted this ?
Reply
Old Sep 24, 2002 | 03:03 PM
  #15  
TonyBurns's Avatar
TonyBurns
Scooby Regular
iTrader: (3)
 
Joined: Aug 2000
Posts: 25,565
Likes: 2
From: 1600cc's of twin scroll fun :)
Unhappy

I had the problem where the pipes to the wastegate needed cleaning out (restricted the flow so wasnt boosting high enough and had an affect like overboosting) so it could be this.

Tony
Reply
Old Sep 24, 2002 | 07:56 PM
  #16  
Moles Dad's Avatar
Moles Dad
Scooby Regular
 
Joined: Feb 2002
Posts: 1,446
Likes: 0
Post

Overboost (fuel cut) is normally associated with boost rising too high due to the colder (more dense) air.

If you have a standard car (mrs. subaru) take it back to dealer and complain.

If you have modded car with de-cat zorst you might want to 'play' with restrictor sizes...not sure that adjusting the wastgate is the answer, but I'm ready to be 'learnt'


Editted due to grammer/vodka problems

If you have an evc...turn it down a bit, if you have a Dawes...turn it down a bit, after all, youll be used to that

Its one of the eccentricities of owning a Scooby

[Edited by Moles Dad - 9/24/2002 7:58:43 PM]
Reply
Old Sep 24, 2002 | 08:16 PM
  #17  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Wink

Moles Dad - The wastegate actuator is the mechanical way of controlling the boosting. My reason is having just replaced my turbo, the old one wasn't as efficient as this new one. The actuator was set-up for the old one hence my over-boosting. Screwed the adjusted one turn outward and so far so good.

I'm open to other suggestions.
Reply
Old Sep 24, 2002 | 09:51 PM
  #18  
grahambeal's Avatar
grahambeal
Scooby Regular
 
Joined: Sep 2002
Posts: 190
Likes: 0
Post

Im having this trouble as well, bloody thing!! nearly got embarased by a Saxo the other night!!! fortunately managed to grab another gear when the boost cut kicked in. Might take my car for a run up to Well Lane and see if they can sort it for me
Reply
Old Sep 24, 2002 | 10:25 PM
  #19  
Moles Dad's Avatar
Moles Dad
Scooby Regular
 
Joined: Feb 2002
Posts: 1,446
Likes: 0
Post

Caz, yeah fully understood

I didnt know it could be utilised to 'correct' ob...but then people do use it to 'higher' boost so yes, I do see it

Good luck everybody
Reply
Old Sep 24, 2002 | 10:31 PM
  #20  
caz1562's Avatar
caz1562
Scooby Regular
 
Joined: May 2002
Posts: 2,148
Likes: 0
From: Scotland
Post

Further to this, I've found code 42 is active - Idle controller, so I'm wondering if this is caused by the overboosting. Can anyone confirm if this is related in some way. If not I'm doing the ECU reset tomorrow and see if fault occur's again.
Reply
Old Sep 25, 2002 | 01:30 AM
  #21  
velryba's Avatar
velryba
Scooby Regular
 
Joined: Apr 2001
Posts: 1,354
Likes: 0
From: Whatever rocks your barge.
Post

and I thought colder weather will give me just a faster ride

I'm kissing the windscreen too....

Now does over boost do any harm to the engine it self?
Reply
Old Sep 25, 2002 | 08:47 PM
  #22  
S3LDM's Avatar
S3LDM
Scooby Regular
 
Joined: Feb 2002
Posts: 2,485
Likes: 2
From: Hunting down door dinger's in south wales..
Question

can overboost cause any damage if not sorted out quickly,
as i suffer from this problem as well

cheers LEE MAC

sorry velryba did'nt see your post, you already asked the question.

[Edited by lee mclaughlan - 9/25/2002 8:51:30 PM]
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
johnmjohnny
Drivetrain
2
Nov 26, 2001 01:26 PM
johnny m
Drivetrain
3
Sep 22, 2001 10:23 PM
john banks
Drivetrain
1
Aug 16, 2001 09:10 PM
simon a
Drivetrain
12
Jul 4, 2001 09:31 AM
Rikki23
ScoobyNet General
5
Jan 8, 2001 03:40 PM




All times are GMT +1. The time now is 07:06 AM.