my 07 bog/lag
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From: Woodland Hills, CA
I'v experianced this too. Funny thing is only when the car was at a lower mileage. I have about 23k on the odometer now and I haven't experianced this anymore. Maybe the ECU adjusted to my driving habits? I have no explanation but it just went away for me. I figured it was DBW related but everybody else on here says otherwise. Whatever it is for me it went away after about 15k miles.
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Originally Posted by armeN,Jul 2 2007, 11:16 AM
I'v experianced this too. Funny thing is only when the car was at a lower mileage. I have about 23k on the odometer now and I haven't experianced this anymore. Maybe the ECU adjusted to my driving habits? I have no explanation but it just went away for me. I figured it was DBW related but everybody else on here says otherwise. Whatever it is for me it went away after about 15k miles.
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From: San Jose, CA
I have an occasional very quick stumble around 2750 rpm when using at least, say 30% throttle. I think there is a hole in the fuel map around this rpm, especially moderate or heavy throttle, and worsening the warmer the weather.
As one poster said, it could be a back up for the CDV mechanism built into the ECU. I suppose that's possible but would be very strange as it happens at such low rpm where there is so little torque anyway, yet not at higher rpms where it might be useful for diff saving purposes.
In any case, a degraded O2 sensor greatly contributes to the problem. Though I never had the O2 sensor CEL, my MY06 kept getting worse and worse regarding the stumble. It use to be that resetting the ECU helped for a while, but even that stopped working.
Finally around 10k miles, I complained to the dealership for the second time about the stumbling. I also pointed them at the TSB. They performed the TSB, which invovles a reflash and a new O2 sensor. The car has been so much better and smoother and more fun to drive now for two thousand miles. It still occasionally stumbles, once per driving session, but learns the problem for the day, though not permanently as it comes back the next day (once though and it learns again).
It apparently needs a good O2 sensor to even see the problem. And with a good O2 sensor, it does learn and adjust. Don't know why it doesn't learn it for good though. It may be that in my case the learning is just outside the range it is willing to commit to permanent memory.
Before the TSB, the stumble was happening more and more and more, and toward the end it was no longer learning at all. I suspect that this is due to the faulty O2 sensor. I don't think they do anything in the ECU reflash except try to protect the O2 sensor. The TSB is about the O2 sensor degrading due to water and simultaneus use of the O2 sensor heater. In the reflash, the ECU stops using the heater when it suspects moisture conditions. (I guess that'd be in the first some seconds after a cold engine start.)
I'd like to try the Bosch replacement sensor when/if it comes available as I've had good luck with using the german sensor in my RX-7. I'm also thinking of trying an apexi neo (piggy back unit) to try to help add fuel around this particular rpm range. Since the car seems willing to add extra fuel once it learns, this might be able to help keep it from forgetting each day.
I'll also point out that having a precsion valve adjustment job helps minimize problems with the stumble. I think that when it hits the lean hole in the fuel map, the more variation there is among the cylinders, the more likely it is that the leanest one of them stumbles worse than the rest.
As one poster said, it could be a back up for the CDV mechanism built into the ECU. I suppose that's possible but would be very strange as it happens at such low rpm where there is so little torque anyway, yet not at higher rpms where it might be useful for diff saving purposes.
In any case, a degraded O2 sensor greatly contributes to the problem. Though I never had the O2 sensor CEL, my MY06 kept getting worse and worse regarding the stumble. It use to be that resetting the ECU helped for a while, but even that stopped working.
Finally around 10k miles, I complained to the dealership for the second time about the stumbling. I also pointed them at the TSB. They performed the TSB, which invovles a reflash and a new O2 sensor. The car has been so much better and smoother and more fun to drive now for two thousand miles. It still occasionally stumbles, once per driving session, but learns the problem for the day, though not permanently as it comes back the next day (once though and it learns again).
It apparently needs a good O2 sensor to even see the problem. And with a good O2 sensor, it does learn and adjust. Don't know why it doesn't learn it for good though. It may be that in my case the learning is just outside the range it is willing to commit to permanent memory.
Before the TSB, the stumble was happening more and more and more, and toward the end it was no longer learning at all. I suspect that this is due to the faulty O2 sensor. I don't think they do anything in the ECU reflash except try to protect the O2 sensor. The TSB is about the O2 sensor degrading due to water and simultaneus use of the O2 sensor heater. In the reflash, the ECU stops using the heater when it suspects moisture conditions. (I guess that'd be in the first some seconds after a cold engine start.)
I'd like to try the Bosch replacement sensor when/if it comes available as I've had good luck with using the german sensor in my RX-7. I'm also thinking of trying an apexi neo (piggy back unit) to try to help add fuel around this particular rpm range. Since the car seems willing to add extra fuel once it learns, this might be able to help keep it from forgetting each day.
I'll also point out that having a precsion valve adjustment job helps minimize problems with the stumble. I think that when it hits the lean hole in the fuel map, the more variation there is among the cylinders, the more likely it is that the leanest one of them stumbles worse than the rest.
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From: Garden City
Originally Posted by Yflyer,Jul 1 2007, 04:38 PM
100% -- my '06, stock, acts totally the same. The Honda tech admitted to me that it is a fuel map problem, and that Honda does not have a fix. I will keep complaining until something is available. My S is a D/D so this is a real PITA.
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From: So Cal
Originally Posted by s2000zr,Jun 30 2007, 11:38 AM
iKMTi, do u do it with vsa on or off? i wonder if there is a way to have vsa off completely or have it off when i start the car and if i want it on, like a rainy day i can turn it on? i hate having to push that button every time i get in the car.
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From: So Cal
Originally Posted by vishnus11,Jul 1 2007, 12:45 AM
For the millionth time...
1. IT IS NOT the delay valve.
2. IT IS NOT VSA
3. This bogging usually occurs between 2000-2750 rpm on 2006 and 2007 vehicles. It feels as if there's a "hole" in the fuel map, where the engine seems to just fall on it face. It's not the DBW system lagging on anything. I had thought that only 06s had this, and thats why Honda changed the ECU for 2007 S2000s but apparently this didn't fix it.
1. IT IS NOT the delay valve.
2. IT IS NOT VSA
3. This bogging usually occurs between 2000-2750 rpm on 2006 and 2007 vehicles. It feels as if there's a "hole" in the fuel map, where the engine seems to just fall on it face. It's not the DBW system lagging on anything. I had thought that only 06s had this, and thats why Honda changed the ECU for 2007 S2000s but apparently this didn't fix it.
So there is no bog problem at all in the year of 00-05???
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Joined: Dec 2000
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From: Charlottesville
Less than 3000 rpm in any model year = very little power. Not bog, just no power. Early on people talked about "kangaroo" starts and severe "bucking". These folks had less power than you do but they learned the idiosyncracies of their car and adapted to them. You will too.
