Notices

Please help;-) Lumpy idle when hot and high co on tick over

Thread Tools
 
Search this Thread
 
Old 30 May 2009, 02:00 PM
  #1  
Tigerfill
Scooby Regular
Thread Starter
 
Tigerfill's Avatar
 
Join Date: May 2009
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Default Please help;-) Lumpy idle when hot and high co on tick over

HI guys thanks for looking first of all great forum ;-) i will start with the car it's a 97 sti v3 has a full decat pipe and vta dump valve panel filter other than those i think its standard!

the Problem!!

When she warms up basicly comes off of choke she almost stalls jumps up to 1100 rpm and drops down again and again and again also i feel she is just holding back a little i have done the ecu check light but it says everything OK

Also i popped into my local mot garage and they tested the co and the co level is around 6.00% on tick over and around 2.5% on fast idle

they think it might be the maf sensor but were unsure!! is there a way i can test the maf or does anyone have any other ideas!!


thanks in advance Phil
Old 30 May 2009, 02:25 PM
  #2  
Tomonsw
Scooby Regular
 
Tomonsw's Avatar
 
Join Date: May 2009
Posts: 38
Likes: 0
Received 0 Likes on 0 Posts
Default Please help;-) Lumpy idle when hot and high co on tick over

If you disconnect the maf while on idle, if the car stalls, its fine, if it keeps running, its no good! This test doesnt always rule out the maf as I was having similar symptoms in MY94 WRX and I did the MAF test and it passed but my prob was still there. I have now cleaned my maf and WOW, what a difference. No more idle issues, no more spluttering or hesitation. A can of CRC electronics cleaner did the trick. Hope this helps. Good luck.

What I also should add is Id done coil packs, plugs, fuel filter, cleaned the pcv, cleaned everything. Nothing fixed it until I cleaned the MAF!

Last edited by Tomonsw; 30 May 2009 at 02:26 PM.
Old 30 May 2009, 02:37 PM
  #3  
TonyBurns
Scooby Regular
iTrader: (3)
 
TonyBurns's Avatar
 
Join Date: Aug 2000
Location: 1600cc's of twin scroll fun :)
Posts: 25,565
Likes: 0
Received 2 Likes on 2 Posts
Default

O2/Lambda sensor could be an issue, you should really get your car on a diagnostics machine, that will point out the problem

Tony
Old 30 May 2009, 03:00 PM
  #4  
STI_Baly
Scooby Regular
iTrader: (23)
 
STI_Baly's Avatar
 
Join Date: Feb 2008
Location: My Workshop, Kent
Posts: 2,588
Likes: 0
Received 1 Like on 1 Post
Default

I had a similar problem which lead to it being a coolant sensor issue, i would check this out and ensure there is no air lock in there.

As said earlier if the MAF is disconnected the car should stall. If it doesn't try using a friends MAF if possible and testing it that way.
Old 30 May 2009, 03:46 PM
  #5  
dj219957
Scooby Regular
 
dj219957's Avatar
 
Join Date: Dec 2003
Location: Staffs
Posts: 3,708
Likes: 0
Received 1 Like on 1 Post
Default

can you clean the maf with water dispersant/penitrating oil or does it have to be brake cleaner?
Old 30 May 2009, 10:29 PM
  #6  
Tigerfill
Scooby Regular
Thread Starter
 
Tigerfill's Avatar
 
Join Date: May 2009
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Default

cheers guys i will try disconnecting it tomorrow

does anyone know a good scooby specialist in the colchester / chemlsford area

thanks Phil
Old 31 May 2009, 01:49 AM
  #7  
Tomonsw
Scooby Regular
 
Tomonsw's Avatar
 
Join Date: May 2009
Posts: 38
Likes: 0
Received 0 Likes on 0 Posts
Default Please help;-) Lumpy idle when hot and high co on tick over

Originally Posted by dj219957
can you clean the maf with water dispersant/penitrating oil or does it have to be brake cleaner?

The safest thing to use is electronic parts cleaner as it doesnt leave any film or residue on the highly sensitive internals of the maf. Ive heard brake and carb cleaner are a bit too harsh. I used electronic cleaner on mine and it cleaned up well and car is running better than ever.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KAS35RSTI
Subaru
27
04 November 2021 07:12 PM
Pro-Line Motorsport
Car Parts For Sale
11
21 November 2015 06:08 PM
Mattybr5@MB Developments
Full Cars Breaking For Spares
12
18 November 2015 07:03 AM
Ganz1983
Subaru
5
02 October 2015 09:22 AM
Baskey
General Technical
3
25 September 2015 03:45 PM



Quick Reply: Please help;-) Lumpy idle when hot and high co on tick over



All times are GMT +1. The time now is 05:39 AM.