OLSD VE adjustments and no change in afr?
02-07-2009, 07:21 PM
#22
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im with him^
by the whole table he was probably talking warm temp all KPAs
ie 80 degrees C and up all MAP kPa
below that you can leave the cold start enrichment in
on mine in OLSD....i have mine all set to 14.63 above 80 kpa i believe....until my car hits 85kpa.....at 85kpa my car should be going into PE anyways....so i have it sloping down from 80 to 95kpa goes from 14.63 to 12.9 then 12.9 from 95 on up
million ways to get a desired result....everyone knows that i dont care how many times you hear one way is the right way
sometimes you gotta quit thinking so techincal and think like your old pal the internal combustion engine....he just wants x fuel x air and x spark and hes happy
by the whole table he was probably talking warm temp all KPAs
ie 80 degrees C and up all MAP kPa
below that you can leave the cold start enrichment in
on mine in OLSD....i have mine all set to 14.63 above 80 kpa i believe....until my car hits 85kpa.....at 85kpa my car should be going into PE anyways....so i have it sloping down from 80 to 95kpa goes from 14.63 to 12.9 then 12.9 from 95 on up
million ways to get a desired result....everyone knows that i dont care how many times you hear one way is the right way
sometimes you gotta quit thinking so techincal and think like your old pal the internal combustion engine....he just wants x fuel x air and x spark and hes happy
02-08-2009, 07:38 AM
#23
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And to the OP, this sounds like a fuel system issue to me...
02-08-2009, 09:06 PM
#24
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Well, for simplicity sake, I said the whole table. 
But yeah, the OLFA table isn't ALL 1's. The results I've gotten were certainly done in open loop, at operating temp. As for a fuel system issue, I was leaning toward that myself, but after the guage install on the end of the fuel rail, it's a constant 62 psi at idle, and doesn't go down but to 58 or so off-idle through the rpm range. I pulled the plugs and they were black. So, now it really doesn't make sense. If I set my VE table closer to the values it "should" be, I bet the car wouldn't even start. I'm with whoever said the motor wants x amount of air with x amount of fuel. I've tried ruling out all possibilities. Here are the results of the leakdown test.
Test done @ 100 psi since thats all my little air compressor would support.
Drivers side front to back % leakdown
15 45 15 43
Pass side front to back
41 45 42 38
The car was cold but the only thing I can compare it to is the last time I did a leakdown test, they ALL were 15% or less. This was about a year and a half ago.
But yeah, the OLFA table isn't ALL 1's. The results I've gotten were certainly done in open loop, at operating temp. As for a fuel system issue, I was leaning toward that myself, but after the guage install on the end of the fuel rail, it's a constant 62 psi at idle, and doesn't go down but to 58 or so off-idle through the rpm range. I pulled the plugs and they were black. So, now it really doesn't make sense. If I set my VE table closer to the values it "should" be, I bet the car wouldn't even start. I'm with whoever said the motor wants x amount of air with x amount of fuel. I've tried ruling out all possibilities. Here are the results of the leakdown test.Test done @ 100 psi since thats all my little air compressor would support.
Drivers side front to back % leakdown
15 45 15 43
Pass side front to back
41 45 42 38
The car was cold but the only thing I can compare it to is the last time I did a leakdown test, they ALL were 15% or less. This was about a year and a half ago.
Last edited by WS6 GreeN; 02-08-2009 at 09:23 PM.
02-09-2009, 05:51 AM
#25
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I would say if you have good fuel pressure and the plugs are black, you either have an air leak in the exhaust that is making the wideband read off, or you are actually very rich - which will make the wideband see lean because of the unburnt fuel (which is oxygenated these days). Does it show lean at WOT, or just at idle and cruise RPMs?
02-09-2009, 10:23 PM
#26
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Interesting idea. I will have to do a little more logging to verify the WOT air/fuel. I know its not the exhaust. I just had a new y-pipe put on with exhaust clamps that cover the joints to make sure it wasn't leaking. That's not to say its not leaking around the header flange or something.
02-10-2009, 11:37 AM
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Some of the cheaper brands of headers have issues with leaks in between the primaries where they go into the collector - because they are not welded very well or on all of the tubes. It is hard to find this unless you have the car in the air running... I'd put my money on an exhaust leak given all the other signs you have...
02-10-2009, 05:04 PM
#31
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?
fix your hardware first. you cannot tune around junk.
02-10-2009, 06:26 PM
#32
Some of the cheaper brands of headers have issues with leaks in between the primaries where they go into the collector - because they are not welded very well or on all of the tubes. It is hard to find this unless you have the car in the air running... I'd put my money on an exhaust leak given all the other signs you have...
Ugh, I have seen this on 3 sets of QTP headers in the last year or so. I don't consider them a cheap brand.
02-12-2009, 11:40 PM
#34
PS, put a new set of plugs in it, set the tune back up the way it was, then approach it differently. This is a common problem, people "tuning around" problems. There's several reasons for it to "look" lean. The 2 basic reasons being, not enough fuel, or too much air.
Also, make sure there's no other odd differences, like it idling in a different cell than it used to. Things like that can clue you in to possible causes. Check the KOEO MAP value to assure the sensor hasn't skewed.
Last edited by edcmat-l1; 02-12-2009 at 11:51 PM.
