Notices
General Technical
Sponsored by:
Sponsored by: CARiD

Accelerating problem (sort of)

Thread Tools
 
Search this Thread
 
Old 15 September 2007 | 03:08 PM
  #1  
simonds1's Avatar
simonds1
Thread Starter
Scooby Regular
 
Joined: Nov 2006
Posts: 639
Likes: 1
From: Pembrokeshire, South Wales
Default Accelerating problem (sort of)

Hey guys, I'll try and describe this problem the best I can okay......

Whenever I'm going along and I try and hold a constant speed, or accelerate very very slightly.....the car seems like it's 'missing' almost? It's very very slight......but like say I'm going up a hill in 2nd following a really slow line of traffic stuck behind a tractor, the car seems to be 'jumping' or 'kangarooing' or whatever you wanna call it. It's not obvious, like the car isn't jumping around in a 'slam on the brakes then let off' style lol, but it's enough that you can feel it hessitating a bit. When you accelerate properly tho, it seems fine. Like say for example I then went to overtake some of this slow moving traffic and just planted my foot in 2nd......it wouldn't hesitate, it would be fine. It's just when I try and accelerate a bit. Weird!

Also, dunno if this could be related, but when it's idling now (when it's warm, after a journey) it kinda does the normal idling burble noise.....but with the odd 'chug' here & there. Quite reqularly, but not at constant intervals. Almost like a 'pop' but not as loud. A little stutter in the exhaust like. Never used to do that. I'll try get it on video maybe at some point if I can be arsed!

Maybe I just need a remap and it'll be fine? I keep wondering if I'm killing the car driving it with my mods now (view my scooby) and no remap. But hoping to get one soon anyway
Old 15 September 2007 | 03:17 PM
  #2  
sl1000's Avatar
sl1000
Scooby Regular
 
Joined: Dec 2005
Posts: 144
Likes: 0
Default

sounds to me that you are feeling the oscillation effect cause by the Lambda regulation.
I also had it when my scoob was still near to standard.
look here for some description.
Untitled
It think all scoobs have it to some effect but due to your mods it might have become more noticable.
You could try changing your Lambda sensor.
Old 15 September 2007 | 03:25 PM
  #3  
simonds1's Avatar
simonds1
Thread Starter
Scooby Regular
 
Joined: Nov 2006
Posts: 639
Likes: 1
From: Pembrokeshire, South Wales
Default

Originally Posted by sl1000
sounds to me that you are feeling the oscillation effect cause by the Lambda regulation.
I also had it when my scoob was still near to standard.
look here for some description.
Untitled
It think all scoobs have it to some effect but due to your mods it might have become more noticable.
You could try changing your Lambda sensor.
Wow cheers for that mate, that seems to make a lot of sense! I think it's only since I've had my ninja sports cat downpipe fitted.....and seeing as the lambda sensor is screwed into that (I think!), right after the turbo, and the 'mouth' of the ninja pipe seems to be slightly more than double the size of the standard subaru one.....I'm sure it would make some kinda difference! I'm guessinga remap would pretty much sort that then?
Old 15 September 2007 | 03:31 PM
  #4  
Mocom Racing's Avatar
Mocom Racing
Former Sponsor
iTrader: (2)
 
Joined: Feb 2005
Posts: 837
Likes: 0
From: workshop tel: 01787 275074
Default

If you have a boost gauge fitted what does it show under these conditions?
Old 15 September 2007 | 03:34 PM
  #5  
sl1000's Avatar
sl1000
Scooby Regular
 
Joined: Dec 2005
Posts: 144
Likes: 0
Default

remap could cure it depending on if the mapper changes the closed loop parameters or let the car run in open loop all the time.
the latter option might give problems with MOT though.
you could also decide to leave it as is since I doubt it to be a real problem (for the engine that is)
for testing purpose you could also do a test run with Lambda sensor disconnected and see if effect is gone. (will make CEL light to come on)
Old 15 September 2007 | 03:36 PM
  #6  
simonds1's Avatar
simonds1
Thread Starter
Scooby Regular
 
Joined: Nov 2006
Posts: 639
Likes: 1
From: Pembrokeshire, South Wales
Default

Originally Posted by Mocom Racing
If you have a boost gauge fitted what does it show under these conditions?
I don't have a boost guage fitted I'm afraid I have only never got one cuz I think it would just look so 'chavvy', havin a boost guage on a completely standard looking car y'know? I don't mean to offend anyone by that, but yeah I just can't think where to put one where it would look decent! I really want to get one tho cuz I'd love to know what's actually happening with the boost. Especially in surcumstances like this where there's actually something wrong, I think it would help a lot.
Old 15 September 2007 | 03:39 PM
  #7  
sl1000's Avatar
sl1000
Scooby Regular
 
Joined: Dec 2005
Posts: 144
Likes: 0
Default

boost gauge should show nothing else than steady vacuum.
the oscillation is caused by changes in mixture due to Closed loop control of the ECU.
Old 15 September 2007 | 03:43 PM
  #8  
sl1000's Avatar
sl1000
Scooby Regular
 
Joined: Dec 2005
Posts: 144
Likes: 0
Default

Originally Posted by simonds1
I don't have a boost guage fitted I'm afraid I have only never got one cuz I think it would just look so 'chavvy', havin a boost guage on a completely standard looking car y'know? I don't mean to offend anyone by that, but yeah I just can't think where to put one where it would look decent! I really want to get one tho cuz I'd love to know what's actually happening with the boost. Especially in surcumstances like this where there's actually something wrong, I think it would help a lot.
best option is center glove compartment in my opinion.
there are several shops which sell a replacement see My scooby for a pic
Old 15 September 2007 | 08:27 PM
  #9  
simonds1's Avatar
simonds1
Thread Starter
Scooby Regular
 
Joined: Nov 2006
Posts: 639
Likes: 1
From: Pembrokeshire, South Wales
Default

Originally Posted by sl1000
best option is center glove compartment in my opinion.
there are several shops which sell a replacement see My scooby for a pic
Aye that is definitely the best place for 'em mate, cuz they don't look 'stuck on', they look like they're meant to be there. But by the time I've bought that centre guage pod, got 3 guages to put in em, and fitted em......that's a lotta money!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
powerwrx
ScoobyNet General
17
04 November 2015 08:18 PM
PetrolHeadKid
Driving Dynamics
10
05 October 2015 06:19 PM
T.K
General Technical
10
02 October 2015 12:35 PM
Lillyart14
ScoobyNet General
24
01 October 2015 02:29 AM
Wish
Computer & Technology Related
3
30 September 2015 11:39 PM



Quick Reply: Accelerating problem (sort of)



All times are GMT +1. The time now is 07:01 PM.