Ignition/Tuner/ECM/Fuel InjectionNeed advice on ignition issues? Questions about a tuner? Have questions about a EFI calibration or Fuel Injection? Tips on Engine Diagnostics, how to get codes, and what they mean. Find your answers here.
I wish I could explain this better, But here goes. Even though the VE's lowered by autotuning seem to be leaner, That's what the sensors are telling AT your engine needs/wants to give it the best mix of air/fuel.
Wether it's shooting for 14.6 while AT'ing, OR whatever AFR values you choose to run afterwards. VE's are just a number the ECM uses to aim for your target AFR with the least amount of +/- up/down corrections when in closed loop areas of your tune, AND outside of closed loop (Open loop). Your AFR table actually determines how rich/lean your finnished tune is. Did that make any sense? Trust AT and let it do it's job/function.
Last edited by Smokey Stover; 07-29-2014 at 08:14 AM.
I wish I could explain this better, But here goes. Even though the VE's lowered by autotuning seem to be leaner, That's what the sensors are telling AT your engine needs/wants to give it the best mix of air/fuel.
Wether it's shooting for 14.6 while AT'ing, OR whatever AFR values you choose to run afterwards. VE's are just a number the ECM uses to aim for your target AFR with the least amount of +/- up/down corrections when in closed loop areas of your tune, AND outside of closed loop (Open loop). Your AFR table actually determines how rich/lean your finnished tune is. Did that make any sense? Trust AT and let it do it's job/function.
Yes, I fully understand that. The VE numbers represent airflow through the engine. The higher the number, more airflow and therefore more fuel correction factor.
Here's what I'm saying... after I run AT sessions, most of the cells I hit in the VE table end up the same or LOWER numbers than those same cells in the factory stock VE tables that my bike came with...yet my air cleaner and exhaust flow WAY more than the stock air cleaner and exhaust. My VE numbers should be, especially in the high load areas, quite a bit higher than those in the factory stock table...otherwise there will not be enough fuel correction for my freer flowing engine. Hence why EVERY custom tune whether it's from FM or DJ has way higher VE numbers than stock. When I run AT on my bike, it basically takes those numbers right back down to or below stock. So that tells me the computer is not getting correct readings during auto tuning and it seems the first likely suspect would be the O2 sensors.
Having the VEs correct is especially important in the open loop areas of a tune where O2s aren't helping out.
Last edited by Red Dragons; 07-29-2014 at 08:37 AM.
/Sigh , I know some of the process seems illogical/ counter intuitive, Like adding fuel/spark advance in deceleration areas to cure popping. Don't get me wrong,No offense intended, But sometimes the problem is the BKAC interface, (Between Keyboard and Chair)(That was my biggest problem) All I can suggest is don't look at the numbers for a few AT runs, Let it tune the bike. Sometimes the values that drop come back up a bit once the whole table has been adjusted/ tuned.You can still run open loop AFR no matter what the VE values are.You might be surprised how well the PV works.
/Sigh , I know some of the process seems illogical/ counter intuitive, Like adding fuel/spark advance in deceleration areas to cure popping. Don't get me wrong,No offense intended, But sometimes the problem is the BKAC interface, (Between Keyboard and Chair)(That was my biggest problem) All I can suggest is don't look at the numbers for a few AT runs, Let it tune the bike. Sometimes the values that drop come back up a bit once the whole table has been adjusted/ tuned.You can still run open loop AFR no matter what the VE values are.You might be surprised how well the PV works.
Adding fuel to get rid of decel popping isn't illogical at all, if you understand how engines work. However my AT results ARE illogical, and as I said earlier in this thread, running an autotuned map is where I first started running into issues. The knocking was worse and the plugs were extremely burned. Since I've gone back to DJ's base VE tables for my bike, I've had less knocking and the new plugs look more like what normal combustion should look like. All signs are pointing to AT causing my bike to run too lean, which I believe is being caused by bad O2 sensors and I'm going to replace them to find out if this is correct. The PV is a good tool but it can only work right if everything else works right.
One thing you can do to keep a close eye on your O2 sensor response is bring up the gauges screen, load your Lambda as 2 of your gauges (front back).. (if you don't know)>Go online and familiarize yourself with Lambda tables vs. AFR (AFR is the ratio-Lambda is the math behind it)
Since you know about what your table is set to AFR wise, watch your lambda and see where things are at. Lambda will also give you a good idea where your voltages are at which is what Stailjim is talking about. The granularity of the Lambda readout is fine in the milli range (voltage is too, but it may be harder to correlate it,, in head,, while riding). Observing the Lambda readings while riding you will (should) notice that number is all over the place, the last digit will be almost unreadable due to the fact that is changing so rapidly. You will also notice that the numbers change from hot to cold motor, hot to cold air etc. This will do the same thing as watching voltage accept that it is easier to connect it to the AFR (14.7=1.000) which you can ensure is inline with expectations, and because the Lambda reading is very precise you should be able to see a bad O2 sensor at the same time. I run my PV in the 6 gauge screen 100% of the time, Lambda are my top 1,2 blocks, Knocks are 3,4, millage is 5 and temp is 6.
One thing you can do to keep a close eye on your O2 sensor response is bring up the gauges screen, load your Lambda as 2 of your gauges (front back).. (if you don't know)>Go online and familiarize yourself with Lambda tables vs. AFR (AFR is the ratio-Lambda is the math behind it)
Since you know about what your table is set to AFR wise, watch your lambda and see where things are at. Lambda will also give you a good idea where your voltages are at which is what Stailjim is talking about. The granularity of the Lambda readout is fine in the milli range (voltage is too, but it may be harder to correlate it,, in head,, while riding). Observing the Lambda readings while riding you will (should) notice that number is all over the place, the last digit will be almost unreadable due to the fact that is changing so rapidly. You will also notice that the numbers change from hot to cold motor, hot to cold air etc. This will do the same thing as watching voltage accept that it is easier to connect it to the AFR (14.7=1.000) which you can ensure is inline with expectations, and because the Lambda reading is very precise you should be able to see a bad O2 sensor at the same time. I run my PV in the 6 gauge screen 100% of the time, Lambda are my top 1,2 blocks, Knocks are 3,4, millage is 5 and temp is 6.
I'll play around with the gauges later today, but I do usually keep Lambda on one of them.
One thing about that table you posted...if that's right then my O2 sensors are beyond ****ed because they have NEVER showed a voltage above 1V with the engine running. Once the engine is shut off, the voltages slowly rise up to 5V, but when running the voltage ranges for both sensors are typically 0.95 - 0.70 This error would make the engine(and PV) think it's running super rich, and would cause the AT results I'm getting.
You have to research the voltages. Everything in that table is spot on from Lambda to the right due to "its math"...... The voltage part may not be, different manufactures, different devices, different ECM units,, etc.etc. I should have just posted a table without the voltages (or maybe this is good, might be what you needed to see to fix issues). I don't actually know if there is a standard for O2 sensors, and that all of them will read the exact same voltage at a given Lambda??? So you would have to find a cut sheet that shows your Lambda slope for your particular O2's.
All that being said, I would think, while not exact, most O2's would work in similar manner voltage wise?? Like anything else a cheep chinee one will have a 20% tolerance, and a high end bosch having a 1%? But they may actually have different voltage standards?? I don't know.
What you just posted does correlate though!,,,, Ton of carbon, PV constantly trying to lean you out, O2 sensor voltage readings OMG rich... Remember though correlation is not causation. :-)
One last thought, you said you VDC are in the .70 - .95 range? If so, does your lambda correlate with the chart above. This would mean your lambda readings would be below 7.XXX??? The good thing is you said when you power off your O2's drift up to 5VDC which is good means they are 0-5VDC so we have the right overall scale.
This is how S#it usually works, swap everything, pull hair out, mess with settings,,pull hair out,, switch back everything,,, pull hair out,,, mess with more settings,,,, pull remaining hair out................ F#@ck bad sensor!
I just took a look at a log from Sunday's ride.I don't think the voltages in that chart are calibrated for the Narrow Band O2 sensors we have in our bikes. They did start up at 5.1 and quickly tapered down to 1.9 to 1.6 on average where my AFR lambda is roughly between .971 and .944 on average cruising range. I only looked at the 2500 RPM- 30-70 KPa where I was cruising at a steady pace ,No AE or DE effecting lambda
The lowest voltage read was 0.84 where my lambda was set at .902 at 3100 RPM and only 10.3 MAP, under heavy deceleration. Like I've said before I ain't the smartest kid in the class, I would like to see that chart with voltages that we know for sure are calibrated for the narrow band sensors.
I just took a look at a log from Sunday's ride.I don't think the voltages in that chart are calibrated for the Narrow Band O2 sensors we have in our bikes. They did start up at 5.1 and quickly tapered down to 1.9 to 1.6 on average where my AFR lambda is roughly between .971 and .944 on average cruising range. I only looked at the 2500 RPM- 30-70 KPa where I was cruising at a steady pace ,No AE or DE effecting lambda
The lowest voltage read was 0.84 where my lambda was set at .902 at 3100 RPM and only 10.3 MAP, under heavy deceleration. Like I've said before I ain't the smartest kid in the class, I would like to see that chart with voltages that we know for sure are calibrated for the narrow band sensors.
Ok well given your numbers I know mine are ****ed for sure. Like I said, mine have never read above 1 volt except when the engine is off, and my lambdas are similar to yours. Also, on hard decel where I have added a ton of fuel to keep the pops down both O2s drop to 0 volts.
I'm gonna buy new sensors from my local dealer for $50 each and go from there.