OLSD VE adjustments and no change in afr?
#1
OLSD VE adjustments and no change in afr?
I have a 02 WS6 M6. I have been running OLSD for a while now. I'm not real sure when this all started, but my VE table needed adjusting according to my LC-1. So, I log a little and make the adjustments to the VE and they're not wanting to change. Some of the cells are up to 120 and still not wanting to cooperate. The MAF is turned off and I decided I'd see if it was just my wideband so I turned ON the O2s. The LTFTs in some places are +10. I was thinking maybe I had an exhaust leak but verified everything under the car was OK. I'm at a loss here as to why the changes I make are not yielding the wanted results. I had heads installed about a year and a half ago. Could I have a leak around the intake or something? Also, the fuel trims don't seem to be bringing the AFR back in line like they should if that helps any. It's still a little lean. TIA.
#3
If you are using HPT try looking at the EQ ratio table:
Engine> Fuel Control> OL&CL> Open Loop “EQ Ratio”
Try setting the values to 1 and see if you AFR changes. If so, then start making changes to your VE. I dont know your setup so I am assuming alot at this point. Such as if you are running SD, that you have upgraded your OS to 1 BAR MAP SD enhanced.
Engine> Fuel Control> OL&CL> Open Loop “EQ Ratio”
Try setting the values to 1 and see if you AFR changes. If so, then start making changes to your VE. I dont know your setup so I am assuming alot at this point. Such as if you are running SD, that you have upgraded your OS to 1 BAR MAP SD enhanced.
#5
#6
Thanks for the replies. First off, the assumption that I'm running the 1bar SD Enhanced OS and HPT is correct.
The OLFA table is set to all 1's also.
And, the WB sensor has been replaced like two weeks ago and hasn't been driven but a few times since. I also suspsected that could've been my problem. I made sure to do the free air calibration outside the exhaust pipe. I can post the tune or logs if I need to.
Doc, the serial cable and the analog input both match up. I have the analog averaging but they seem to be the same.
I might also need to point out that at idle, the afr is around 17-18:1. I know its not as accurate at idle but that still sounds quite high to me.
The OLFA table is set to all 1's also.
And, the WB sensor has been replaced like two weeks ago and hasn't been driven but a few times since. I also suspsected that could've been my problem. I made sure to do the free air calibration outside the exhaust pipe. I can post the tune or logs if I need to.
Doc, the serial cable and the analog input both match up. I have the analog averaging but they seem to be the same.
I might also need to point out that at idle, the afr is around 17-18:1. I know its not as accurate at idle but that still sounds quite high to me.
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#9
OK I will have to get the logs tomorrow after I bring home my flash drive. But, I did get to do a little more messing around today. At idle, it was ~18:1 afr. Ve table was bouncing between the 800-1200 cells @ about 50kPa I believe. I had to change the VE table by about 35 (which put that cell at about 115) to get it down to a decent air/fuel. I know this probably just complicates things but I thought I'd post it up while I was thinking about it.
#11
Ya know, that probably wouldn't be a bad thing to check. I've read that you can get the gauge to go on the end of the fuel rail. Can you give me a little more info on where I can get that and if I need an adapter? I'll search and see what I can find. Thanks.
#12
OK I bought a gauge and checked the fuel pressure today. It was about 48 psi when I turned the key on to prime it. I couldn't start it because its sort of taken apart right now. As soon as its back together I will see what it is then. I just installed a walbro 255 with the racetronix stuff about 9 months ago because the pump just up and stopped working one day so I don't know how it could be a pump problem. Any ideas on that?
#13
I have have a very similar problem. OL SD Tune. We have been trying to mess with my VE tables to get my AFR right, but doesn't seem to be working. My EQ Ratio table is not set to 1 though. I also want to add that my fuel pressure seems to be kind of low. I also noticed that at wide open throttle my system voltage drops. Maybe this could be a low voltage problem also? How is you voltage reading?
#14
That seems wrong to me, I could see putting 1.0 in the areas of idle and cruise, but you'd want it richer than that in other areas so you'll have a smoother transition from the OLFA table to PE. Or at least I'd think you would, but I don't know much.
#16
#17
The car will drive just fine with the OLFA set to 1. Maybe not as good as it could be but definitely good enough to fix AFR error.
#18
Dude, I know you've been tuning for 2 weeks now, but that's obvisouly not this guys issue. He is showing 17-18 AFR, he wouldn't be driving anywhere if that were the real values, regardless of how or what is being commanded.
The car will drive just fine with the OLFA set to 1. Maybe not as good as it could be but definitely good enough to fix AFR error.
The car will drive just fine with the OLFA set to 1. Maybe not as good as it could be but definitely good enough to fix AFR error.
There are plenty that have been tuning for years and still spreading BS information.
#19
There's more to tuning that just reading and following someone else's ways. In closed loop the PCM is try it's damnedest to keep AFR at Stoich. Makes you wonder huh?
I also know that it don't ******* matter here. This guy has been running OLSD for a while and all of sudden started having problems. OLFA tables don't change themselves. Which was my point to begin with. He needs to get this problem fixed before he worries about anything else.
Last edited by JonCR96Z; 01-24-2009 at 11:25 PM.
#20
You'd likely never know the difference on most cars. If the car likes it, then yes it's fine. If the car like something else, then use that. That's why they call it tuning. How do I know, I've seen and done it.
There's more to tuning that just reading and following someone else's ways. In closed loop the PCM is try it's damnedest to keep AFR at Stoich. Makes you wonder huh?
I also know that it don't ******* matter here. This guy has been running OLSD for a while and all of sudden started having problems. OLFA tables don't change themselves. Which was my point to begin with. He needs to get this problem fixed before he worries about anything else.
There's more to tuning that just reading and following someone else's ways. In closed loop the PCM is try it's damnedest to keep AFR at Stoich. Makes you wonder huh?
I also know that it don't ******* matter here. This guy has been running OLSD for a while and all of sudden started having problems. OLFA tables don't change themselves. Which was my point to begin with. He needs to get this problem fixed before he worries about anything else.