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Would like to report that I fixed this issue on my car. It turns out that it was my rear o2's causing the issue due to the test pipes. I completely over looked and ignored this being a cause because I didn't realize that these modern ECU's actually do use the rear o2's data for fueling. The fix for me was 90 degree angled spacers on the test pipes. No more CEL, hesitation, lag or bogging anymore.
This would make some sense as to what you are experiencing. I have failing cats with 420&430 being triggered. Once I trigger one of these the car runs different, sluggish.
I normally keep my tablet in the car and clear it, just comes on after 15 mins of driving, once it's cleared you're good for the day.
This lagging feeling can be interpreted as a throttle lag however if you pay attention to the tablet you'll see it's fuel and timing being altered. If the feeling you guys are complaining about is what I feel with a p0430 or p0420 then what Juster said might be a cheap possibility to try out.
Would like to report that I fixed this issue on my car. It turns out that it was my rear o2's causing the issue due to the test pipes. I completely over looked and ignored this being a cause because I didn't realize that these modern ECU's actually do use the rear o2's data for fueling. The fix for me was 90 degree angled spacers on the test pipes. No more CEL, hesitation, lag or bogging anymore.
Once I trigger one of these the car runs different, sluggish.
Exactly. This is how I finely noticed. Right as soon as the light comes on is when it would experience the problem. Sure here you go. I got mine on ebay but it looks like that seller is out of them, here is a link for amazon. I have them pointed back towards the engine. This amazon one has an extra spacer included on the end which my ebay one didn't have but maybe nice to have if you need more space. I run mine like the bottom picture with the sensor directly in the spacer without the extra piece.
We might be onto something then. I can say I would hate if the car performed the way it did with these lights on.
Makes sense with what you guys are experiencing. Worse if you have HFCs or test pipes without fowlers or without a tune.
The O2s would make the ECU crazy
Not an expert, but usually what people deem to be throttle lag is really just the car driving the way it was programmed to drive for emissions and gas reasons. If you leave your transmission in regular drive mode, it takes time to move between gears (always stays as low in the revs as possible) and will always prioritize gas savings over performance, which is why as soon as you need a bit of power, you have to wait a second for the transmission to shift down 1-2 gears and then put the power down.
If you throw it in sport mode, it gets a little better because now it is finding a middle ground where, it will tend to stay calm if you drive calm, but once you start driving aggressively, the computer automatically keeps the transmission 1-2 gears lower than would be optimal for gas/emissions. If you slam on the gas pedal and rev it to 5K, the transmission will stay in that gear for 3-4 seconds waiting for you to just slam the gas pedal down again and push you forward.
Then, if you want total control, the sequential mode of the car gives you that. You can choose what revs you want to be at in what gear in whatever speed you want. That is why people deem manual transmissions to be more responsive, simply because you can choose to keep it at a gear/rev range that is more responsive than 1.5K at whatever speed you are going. I'd say that if you go on the highway, throw the car into manual mode and your still seeing serious throttle lag, you can probably take a few steps to alleviate that: i.e. making sure you have fresh filters, airflow sensor fully operational, cleaning throttle bodies, etc, etc... However, in the end of the day, there is a limitation to the responsiveness of drive-by-wire vehicles. For the time being, drive-by-wire will almost always have at least a tiny bit more throttle delay when compared to drive-by-cable (not that the G37 6MT has that).
EDIT: forgot to note, there is a more aggressive option that people say helps alleviate throttle lag if performance is 100% all you want from your car, certain tunes will help with the lag, not exactly sure by what mechanism they do that, but I do know they exist, and I know some people stand by them.
