Drivetrain HELP!!- 06s running WAY to lean!!
#26
06-23-2010 | 09:10 AM
6th Gear
Joined: Mar 2006
Posts: 1,710
Likes: 1
From: Northampton MA
The fuel pump and filter are rarely the problem. It can happen, but it's rare.
Some posts have questioned whether your testing methods are giving you true results (if you car is actually running lean). White plugs and lean conditions at the tailpipe is irrefutable evidence that you have a problem. The AFRs from a tailpipe sensor will be no more than .5 ratio difference from the upstream O2 sensor: it will not 'show lean' because it's been through the cats.
I like the suggestion to go to some factory injectors and see if that solves your problem. Except for extreme tuning projects, 550cc injectors are very big: you could be running into scaling issues.
Some posts have questioned whether your testing methods are giving you true results (if you car is actually running lean). White plugs and lean conditions at the tailpipe is irrefutable evidence that you have a problem. The AFRs from a tailpipe sensor will be no more than .5 ratio difference from the upstream O2 sensor: it will not 'show lean' because it's been through the cats.
I like the suggestion to go to some factory injectors and see if that solves your problem. Except for extreme tuning projects, 550cc injectors are very big: you could be running into scaling issues.
Just out of curiousity where does the OE get the data to adjust the AF if not from the upstream O2?? On my car it's in front of the pre-cat - stock header.
#28
06-26-2010 | 08:43 AM
Attachment 48240
Here is a pic of the o2 sensor on the mynes header- could my problem be that the sensor is not at the 10-12 oclock position-??
Here is a pic of the o2 sensor on the mynes header- could my problem be that the sensor is not at the 10-12 oclock position-??
Anyway, that's the post cat O2 so it should have nothing to do with AFRs. (I may be wrong of course).
Thought you were bringing it down to Helix?
#30
06-28-2010 | 08:57 PM
5th Gear
Joined: Mar 2005
Posts: 779
Likes: 0
We had been chasing a similar issue (on one of the race car so use it for what it's worth on a street car). The Fuel pressure was within specs but at the low end of the scale. 2 things fixed the problem. A) Bad ground on the pump (we obviously have modified factory wiring) and B) Replaced the fuel pump.
Suggestions only, use it for what it's worth.
Suggestions only, use it for what it's worth.
Thread
Thread Starter
Forum
Replies
Last Post
Kimolaoha
R56 :: Hatch Talk (2007+)
5
12-05-2020 09:32 PM
imanexcellentdriver
1st Gen Countryman (R60) Talk (2010-2015)
10
08-31-2015 08:08 PM