B5 Models Please discuss all 1996 - 2001 B5 A4 topics here...

VAG COM misfire/too lean

Thread Tools
 
Search this Thread
 
  #1  
Old 04-22-2008, 09:08 PM
Apdl's Avatar
Member
Thread Starter
Join Date: Jul 2007
Location:
Posts: 66
Default VAG COM misfire/too lean

Hi All,

It has been a while and finally got the old Audi checked out.
Here is what it told me...

Fuel Trim; Bank 1 (Multi): System too Lean
P1128 - 35-00 - -
Then some misfire stuff
P0300 - 35 -00 - - - Intermittent

P0301 - 35 -00 - - - Intermittent

P0303 - 35 -00 - - - Intermittent

P0304 - 35 -00 - - - Intermittent
Readiness: 0010 1001

The ceck engine light has been on for a while and when I cleaned the MAF it was gone for like 2 weeks now 6 mo later it is still on

I ordered new plugs and fuel filter
If that dosent work then check for leaks, Coil Packs, O2 sensor cleaning/replacement then I am going to need your help! what is your take on this?
 
  #2  
Old 04-22-2008, 09:39 PM
machetetooth's Avatar
1st Gear
Join Date: Feb 2008
Location:
Posts: 77
Default RE: VAG COM misfire/too lean

I would start by testing your MAF sensor by running to 6500 in second gear while logging your air mass flow rate in the vagcom. Divide the highest flow rate by .8, and that should be around 170 hp. If it's less, somethings up. My xd45 goes bang louder.
 
  #3  
Old 04-22-2008, 10:21 PM
Apdl's Avatar
Member
Thread Starter
Join Date: Jul 2007
Location:
Posts: 66
Default RE: VAG COM misfire/too lean

Ok I will see what I can do with that
Thanks
PS. my P22 goes meow
 
  #4  
Old 04-22-2008, 10:32 PM
01AudiA4's Avatar
2nd Gear
Join Date: Aug 2007
Location:
Posts: 685
Default RE: VAG COM misfire/too lean

My fist goes faster than your bullets.
 
  #5  
Old 04-22-2008, 11:38 PM
Apdl's Avatar
Member
Thread Starter
Join Date: Jul 2007
Location:
Posts: 66
Default RE: VAG COM misfire/too lean

Right...
Now for something constructive...
 
  #6  
Old 04-23-2008, 12:08 AM
cincyTT's Avatar
I'm make believe
Join Date: Dec 2006
Location: In my head
Posts: 17,587
Default RE: VAG COM misfire/too lean

That is usually a bad primary o2 or vac leak.
 
  #7  
Old 04-23-2008, 02:13 AM
Apdl's Avatar
Member
Thread Starter
Join Date: Jul 2007
Location:
Posts: 66
Default RE: VAG COM misfire/too lean

Vac leak would be a whole lot cheaper than an O2
BTW what is the formula for HP from MAF?
 
  #8  
Old 04-23-2008, 03:32 AM
david9999's Avatar
4th Gear
Join Date: Jul 2004
Posts: 4,354
Default RE: VAG COM misfire/too lean

I don't have my Bently with me, but in the usual germanic way of doing things AUDI reads out basackward. As I recall, "System too lean" actually means that the control system has exceeded the amount that it can lean the mixture in response to the engine running rich.

Made sense to someone.. Anyway, if someone can look up the P1128 trouble shooting procedure in their Bently, I would bet that it would tell you to change the oxygen sensor.
 
  #9  
Old 04-26-2008, 09:10 AM
Apdl's Avatar
Member
Thread Starter
Join Date: Jul 2007
Location:
Posts: 66
Default RE: VAG COM misfire/too lean

Can someone check on this?

 
  #10  
Old 04-27-2008, 06:02 PM
machetetooth's Avatar
1st Gear
Join Date: Feb 2008
Location:
Posts: 77
Default RE: VAG COM misfire/too lean

ORIGINAL: david9999

I don't have my Bently with me, but in the usual germanic way of doing things AUDI reads out basackward. As I recall, "System too lean" actually means that the control system has exceeded the amount that it can lean the mixture in response to the engine running rich.

Made sense to someone.. Anyway, if someone can look up the P1128 trouble shooting procedure in their Bently, I would bet that it would tell you to change the oxygen sensor.
Are you pretty sure about this? After a vociferous argument I just had with a 225 hp TT owner who has the same code, I really hope you're mistaken. Not to hijack the thread, but his MAF maxes out at 99 g/s, which is why I thought it was probably the MAF or vac leak making it lean.

Apdl, the hp formula is the one where you divide your peak air mass flow rate by 0.8. I got it from the 1.8t troubleshooting guide thread. GL
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
campbellpt
Audi TT
0
12-14-2013 11:43 PM
KJNY2
Audi A4
1
09-25-2011 10:40 AM
on_6mt
B6 Models
7
08-18-2009 12:00 PM
919industries
B6 Models
7
06-30-2008 11:13 PM



Quick Reply: VAG COM misfire/too lean



All times are GMT -4. The time now is 07:02 AM.