Really Unusual O2 problem
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Really Unusual O2 problem
Hello,
I've got my car tuned in really well in a locked BLM INT chip. The reported AFR vs RPM vs MAP looks wonderful and follows my desired AFR table perfectly.
This is a problme though as the car has no direct feedback from the o2's. This is a problem because on really cool days or really warm days I can notice a difference in driveablity. This car sits for months at a time too so If I tune it last in febuary and drive it in July... theres a difference..
Ok.. that being said..
The o2's in the car I assumed where fouled out from alot of alcohol use and 1 to many other misc foulings.. They consistantly read too high (indicated rich)
I replaced the o2's today and to my surpize I get the exact same numbers.. While my wideband is reading 14.7 the BLM's and INTs nose dive taking the afr so lean that I get lean pops and horrible driveiblity.
By unlocking the BLM/INT's and letting the car use feedback from the o2's I've completely destroyed any hope in driveablity.. If I lock them back to 128 the driveablity gets perfect again.
What the heck can cause rich o2 readings on a lean car? I know misfires and exhaust leaks with show up lean.. but nothing I know of will show up rich.
The wideband and the narrow bands are mounted about 4 inches apart. The narrowbands are unheated and I do have long tubes but this has never been a problem when the car was all motor.
I've got my car tuned in really well in a locked BLM INT chip. The reported AFR vs RPM vs MAP looks wonderful and follows my desired AFR table perfectly.
This is a problme though as the car has no direct feedback from the o2's. This is a problem because on really cool days or really warm days I can notice a difference in driveablity. This car sits for months at a time too so If I tune it last in febuary and drive it in July... theres a difference..
Ok.. that being said..
The o2's in the car I assumed where fouled out from alot of alcohol use and 1 to many other misc foulings.. They consistantly read too high (indicated rich)
I replaced the o2's today and to my surpize I get the exact same numbers.. While my wideband is reading 14.7 the BLM's and INTs nose dive taking the afr so lean that I get lean pops and horrible driveiblity.
By unlocking the BLM/INT's and letting the car use feedback from the o2's I've completely destroyed any hope in driveablity.. If I lock them back to 128 the driveablity gets perfect again.
What the heck can cause rich o2 readings on a lean car? I know misfires and exhaust leaks with show up lean.. but nothing I know of will show up rich.
The wideband and the narrow bands are mounted about 4 inches apart. The narrowbands are unheated and I do have long tubes but this has never been a problem when the car was all motor.
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From: In reality
Car: An Ol Buick
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Re: Really Unusual O2 problem
Originally posted by rooster433
While my wideband is reading 14.7 the BLM's and INTs nose dive taking the afr so lean that I get lean pops and horrible driveiblity.
The wideband and the narrow bands are mounted about 4 inches apart. The narrowbands are unheated and I do have long tubes but this has never been a problem when the car was all motor.
While my wideband is reading 14.7 the BLM's and INTs nose dive taking the afr so lean that I get lean pops and horrible driveiblity.
The wideband and the narrow bands are mounted about 4 inches apart. The narrowbands are unheated and I do have long tubes but this has never been a problem when the car was all motor.
WBs have their own *heaters*, and if they're reading one AFR, and the unheated one, is way off (even when new), then that would seem to point out that you need another heated one.
If you're using Bosch O2s, just be sure to get Delco A/Cs for the heated ones.
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Code:
Average BLM sample value per cell 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 400.0 500.0 116.0 600.0 700.0 108.0 800.0 109.2 108.0 108.0 108.0 900.0 109.3 108.0 108.0 108.0 108.0 1000.0 108.0 109.3 108.0 108.0 108.2 108.0 1100.0 108.0 108.3 108.0 108.2 108.1 1200.0 108.4 108.1 108.0 109.0 108.1 1300.0 109.0 108.6 108.0 112.1 108.3 1400.0 109.4 108.2 109.6 111.2 108.0 1500.0 109.6 108.0 111.4 109.3 108.0 1600.0 109.0 108.9 111.3 108.5 108.0 1700.0 108.6 112.3 110.2 108.2 108.0 1800.0 108.0 109.6 110.0 108.0 108.0 1900.0 109.9 108.2 108.5 108.0 108.0 2000.0 110.0 109.7 108.2 108.0 108.0 2200.0 109.5 109.6 110.9 108.0 108.0 2400.0 109.1 108.1 108.0 108.0 2800.0 110.7 114.7 117.9 108.0 3200.0 115.0 112.3 108.0 3600.0 4000.0 4500.0 5000.0 5500.0 6000.0 6500.0 7000.0 Average O2 sample value per cell 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 400.0 500.0 506.0 600.0 700.0 948.0 800.0 680.3 941.0 910.1 510.5 900.0 566.8 668.2 648.8 582.9 345.5 1000.0 886.0 611.9 590.8 288.0 484.6 319.5 1100.0 860.3 584.0 523.3 454.3 428.2 1200.0 695.8 534.0 479.4 399.3 576.1 1300.0 754.0 585.9 410.0 493.4 697.4 1400.0 754.8 592.0 543.0 749.6 846.2 1500.0 732.2 711.8 505.7 484.4 901.3 1600.0 616.6 703.6 546.3 290.2 793.1 404.0 1700.0 815.9 734.9 538.2 202.8 763.8 1800.0 627.0 666.2 646.8 181.1 796.0 1900.0 573.4 614.0 518.0 147.0 586.0 2000.0 523.2 547.0 576.0 629.6 800.5 2200.0 586.4 534.8 587.7 480.8 590.5 2400.0 404.1 550.2 567.8 481.5 2800.0 662.0 670.6 793.5 527.2 3200.0 184.0 438.7 408.2 3600.0 4000.0 4500.0 5000.0 5500.0 6000.0 6500.0 7000.0 Average Wideband AFR sample value per cell 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 400.0 500.0 600.0 700.0 800.0 14.1 900.0 14.5 14.7 14.7 1000.0 14.8 14.3 15.0 14.9 1100.0 15.2 14.6 15.1 14.8 1200.0 14.0 14.9 15.2 15.1 14.7 1300.0 14.1 14.7 15.3 14.8 14.3 1400.0 14.2 14.8 15.1 14.4 14.0 1500.0 14.0 14.4 15.1 15.1 13.5 1600.0 14.5 14.4 14.8 15.5 1700.0 13.8 14.2 14.6 15.4 1800.0 14.7 14.1 14.5 15.3 1900.0 14.9 14.3 14.5 15.3 2000.0 15.1 14.5 14.5 14.3 2200.0 14.8 14.4 14.3 14.4 2400.0 15.5 14.7 14.7 14.4 2800.0 14.3 14.0 13.8 14.5 3200.0 14.5 3600.0 4000.0 4500.0 5000.0 5500.0 6000.0 6500.0 7000.0
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Re: Re: Really Unusual O2 problem
Originally posted by Grumpy
My first move would be installing a heated O2.
WBs have their own *heaters*, and if they're reading one AFR, and the unheated one, is way off (even when new), then that would seem to point out that you need another heated one.
If you're using Bosch O2s, just be sure to get Delco A/Cs for the heated ones.
My first move would be installing a heated O2.
WBs have their own *heaters*, and if they're reading one AFR, and the unheated one, is way off (even when new), then that would seem to point out that you need another heated one.
If you're using Bosch O2s, just be sure to get Delco A/Cs for the heated ones.
Thats the part that I find highly unusual.
the post above is a spit out of a little excel worksheet I built to handle CSV dumps. It puts info in a graphical since making it easier to read.
It is from a log today in which I raised the rich/lean threshold vs. Gram/sec vs o2 value. The reason why I did this is because i believe my Gram/sec calculation is still screwed from my 2 bar $DA3 hack.
**********
As you can see, that the AFR's are starting to come in line... HOWEVER This is only because I raised the O2 threashold for rich lean.. Look at the NB samples.. they are consistantly in the 600-700's yet the afr is typoically in the high 14's to even early 15's.
**********
Last edited by rooster433; Aug 24, 2005 at 10:48 AM.
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Looking over the data again I feel that the proper soulution will be for me to -rehandle- the Gram/sec calibration. As you can see, its still targeting a unusually lean AFR per load.
** you got to remeber that this is a universal DA3 calcuator i built and i'm currently running half the resoulution so 50KPA actually = 100KPA**
Either that or *rehandle* the rich/lean threashold which is fairly difficult because of the stock NB's non-linear output. What I can do is build anthor worksheet that looks at AFR vs. O2 output and pick my thresholds accordingly.
** you got to remeber that this is a universal DA3 calcuator i built and i'm currently running half the resoulution so 50KPA actually = 100KPA**
Either that or *rehandle* the rich/lean threashold which is fairly difficult because of the stock NB's non-linear output. What I can do is build anthor worksheet that looks at AFR vs. O2 output and pick my thresholds accordingly.
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Originally posted by rooster433
Looking over the data again I feel that the proper soulution will be for me to -rehandle- the Gram/sec calibration. As you can see, its still targeting a unusually lean AFR per load.
** you got to remeber that this is a universal DA3 calcuator i built and i'm currently running half the resoulution so 50KPA actually = 100KPA**
Either that or *rehandle* the rich/lean threashold which is fairly difficult because of the stock NB's non-linear output. What I can do is build anthor worksheet that looks at AFR vs. O2 output and pick my thresholds accordingly.
Looking over the data again I feel that the proper soulution will be for me to -rehandle- the Gram/sec calibration. As you can see, its still targeting a unusually lean AFR per load.
** you got to remeber that this is a universal DA3 calcuator i built and i'm currently running half the resoulution so 50KPA actually = 100KPA**
Either that or *rehandle* the rich/lean threashold which is fairly difficult because of the stock NB's non-linear output. What I can do is build anthor worksheet that looks at AFR vs. O2 output and pick my thresholds accordingly.
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I've never heard of that either though if it's any consolation. Even when an o2 fails, it fails lean.
I've never heard of that either though if it's any consolation. Even when an o2 fails, it fails lean.
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Thanks,
Yeah, thats how I know them failing too.. although I'm begging to think that when they go cold they progressively read richer and richer.
I got heated AC delcos going in tomarrow/ thursday.. that will hopefully shed some light on things
Yeah, thats how I know them failing too.. although I'm begging to think that when they go cold they progressively read richer and richer.
I got heated AC delcos going in tomarrow/ thursday.. that will hopefully shed some light on things
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From: In reality
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Originally posted by rooster433
How can that happen in 5 minutes of run time?
How can that happen in 5 minutes of run time?
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Originally posted by rooster433
Code:
Average BLM sample value per cell
If you want to use the oem estimates of what the average AFR is, is one thing, but to try and compare it to another *average*, is something I wouldn't do. The stock O2 is just trying to average an AFR by toggling across a thershold, it's not averaging the output voltage, like a WB does. So you're kind of, at least in my view, comparing apples and oranges.
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Originally posted by Grumpy
Looking at the NB O2 mv, vs the WB AFR shows how their not even closely (IMO) related, other then *sort of* at stoich.
If you want to use the oem estimates of what the average AFR is, is one thing, but to try and compare it to another *average*, is something I wouldn't do. The stock O2 is just trying to average an AFR by toggling across a thershold, it's not averaging the output voltage, like a WB does. So you're kind of, at least in my view, comparing apples and oranges.
Looking at the NB O2 mv, vs the WB AFR shows how their not even closely (IMO) related, other then *sort of* at stoich.
If you want to use the oem estimates of what the average AFR is, is one thing, but to try and compare it to another *average*, is something I wouldn't do. The stock O2 is just trying to average an AFR by toggling across a thershold, it's not averaging the output voltage, like a WB does. So you're kind of, at least in my view, comparing apples and oranges.
And thats why I included average BLM. The average o2 is just to see what happens. The average NB o2 is a indication that there is a problem because you can tell from the data that its spending most its time at high V's (most of that being over 800) I expect to not see 450 but something between 350-550 in most cells should be excpected
Unless somehow magically my desired AFR got swapped to about 16.5 to 1 you can clearly see that I have a problem.
Last edited by rooster433; Aug 31, 2005 at 09:07 AM.
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Originally posted by rooster433
i'm pretty much throwing that away.. Theres no silicone in my engine anywhere..
i'm pretty much throwing that away.. Theres no silicone in my engine anywhere..
RBob.
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Oh man, now that's crazy.....
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Originally posted by rooster433
RBob.
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Originally posted by rooster433
So what do you not believe me that the motor that I personally put together is not with a sensor safe RTV? That the radiator is full of water (this is not a daily driver and it doesn't get cold here)
So what do you not believe me that the motor that I personally put together is not with a sensor safe RTV? That the radiator is full of water (this is not a daily driver and it doesn't get cold here)
However, I would imagine that because this can't be the problem, that you are going to post that no silicon has ever been in the area of your car. . .
Whatever. . .
RBob.
P.S. Just remember that you are the one that asked about an O2 sensor reporting rich when in fact the engine AFR is lean. And again, search for the truth.
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Got everything peachy
heres how...
I swapped to heated o2's
This made things way more consistant especially at prolong idles.. Whereas before the 02's woudl creep cold until and idle quality degraded until the ECM threw it back into open loop. This was expected.. Only reason why I didn't do it sooner is because I have just grown acustomed to not using o2's at all.
Rescaled GM/SEC threshholds
This was something I had forgotten about in my original 2 bar hack. IN otherwords the desired AFR per GM/Sec was badly skewed and after a few hours of data interpetation I managed to find something really really nice
Rescaled MAP Cell bounderys
Again, anthor little tidbit I didn't think about when using a 2 bar map sensor. I had previously cut the values in half but there was much much more to getting it to handle decel, idle, moderate load, light load, heavy load, etc..
I'm reviewing a 11,000 record datalog right now and the highest devation from 128 i'm seeing is around >4% without any tuning after tuning with the wideband.
I'm real pleased at this point.. other than a light decel issue caused by the car maxing out the lower limits of the map sensor (hitting 14.4kpa indicated by datamaster) i'm pretty much done. The car is driving exceptionally smooth and falling into PE very nicely. It honestly feels like it could have come from the factory with this setup.
this 2 bar thing has been almost a 3 year work in progress.
heres how...
I swapped to heated o2's
This made things way more consistant especially at prolong idles.. Whereas before the 02's woudl creep cold until and idle quality degraded until the ECM threw it back into open loop. This was expected.. Only reason why I didn't do it sooner is because I have just grown acustomed to not using o2's at all.
Rescaled GM/SEC threshholds
This was something I had forgotten about in my original 2 bar hack. IN otherwords the desired AFR per GM/Sec was badly skewed and after a few hours of data interpetation I managed to find something really really nice
Rescaled MAP Cell bounderys
Again, anthor little tidbit I didn't think about when using a 2 bar map sensor. I had previously cut the values in half but there was much much more to getting it to handle decel, idle, moderate load, light load, heavy load, etc..
I'm reviewing a 11,000 record datalog right now and the highest devation from 128 i'm seeing is around >4% without any tuning after tuning with the wideband.
I'm real pleased at this point.. other than a light decel issue caused by the car maxing out the lower limits of the map sensor (hitting 14.4kpa indicated by datamaster) i'm pretty much done. The car is driving exceptionally smooth and falling into PE very nicely. It honestly feels like it could have come from the factory with this setup.
this 2 bar thing has been almost a 3 year work in progress.
Last edited by rooster433; Sep 8, 2005 at 04:24 PM.
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