February 5th, 2010, 08:23
Is before 1 and before 2 the 2 different banks? Or 2 different runs?
February 5th, 2010, 14:25
I should have been more clear. Numbers shown on the graph are the absolute values of the percent difference between the banks, 1 and 2 are different runs.
February 5th, 2010, 15:18
You should work in the dept of treasury
February 5th, 2010, 15:25
I don't think the difference between the 2 is terribly critical, unless it's huge of course. Which in your case it kinda is. If the g/s reading is proportional to the actual amount of air flowing in then the lambda correction should do its job. Which brings me to what I'm having an issue with.
Measuring block one shows lambda control. Which goes to ZERO under WOT - we have seen this. So:
1. What determines WOT? We've seen that it's not throttle valve angle (at least not only this), there must be other factors.
2. What about the multiplicative lambda values? These are learned over a period of time (I'm guessing minutes). Do these still apply under WOT? I'd say yes.
3. Under part throttle, the multiplicative lambda values are in play, but also the lamdba control values in MB001. Is this a fine tune device?
Virtual beer (or chicken dinner as I suspect it might turn out to be) to he who gives a convincing answer
February 8th, 2010, 09:13
Any progress on this? What's the verdict on the new MAFs?
February 8th, 2010, 13:41
I haven't double checked to see if my error codes are gone, but after replacing the MAF's and N75, the car feels much better, the variance between banks is well under 10% across the range and the total MAF is reading more like what it should in total (Bank1+2).
A crude, hasty 0-60 time on VAG-COM showed 5.2, well under the mid to high 5's previously, so big improvement. Further, put it on the dyno Friday and it showed to be making right at 450hp with a smooth power curve. So, I think I've fixed it.
Not sure how convincing my answers will be but I'll try:
1. Throttle position sensor, but maybe load instead?
2. I agree, yes
3. Again yes.
Last edited by RS6-4dr911; February 8th, 2010 at 13:52.
February 8th, 2010, 14:10
That sounds quite encouraging. I've got my new MAFs now and will install them at the same time as the N75 when I get a chance. I'll let you know (though not for a while - too busy to play )
February 16th, 2010, 15:25
Any update on this Shoppinit?
Originally Posted by Shoppinit
February 16th, 2010, 15:27
Still haven't had time to play. I might get a chance on Thursday. I'm not really expecting any improvement since my logs look good and I recently got full power on the rollers. Might be interesting to see what happens though. I'll be keeping the old MAFs as spares.
Are you having issues?
February 16th, 2010, 15:45
No codes but not making full power just beginning to investigate. Boost looks lower than requested as tested this morning.