[ndog14]

Originally Posted by MrDummy

^^^ I am not sure? Im still waiting and searching to see what engine i have for sure!!!

Can't you just look at the emissions sticker under the hood of the car? It will say SULEV or ULEV.

[MrDummy]

I can do that, i did not know where it was. Thanks.

[SyracuseVince]

I hope I'm not too off-topic ... was happy to find a related thread with some current activity.

I have a 18 month-old e92 SULEV, manual transmission, RWD. I've been quite happy with it. I recently noticed behavior I find odd. In all gears but 3rd, when you let off the gas pedal, the throttle closes (completely) and reopens at about 1000 rpm (just in time for idle). In 3rd gear the throttle opens for idle at 2600 rpm. This causes a noticeable instantaneous decrease in deceleration and continued decreased deceleration thereafter). All this can be verified beyond a doubt by watching the instantaneous gas mileage display. When engine braking in any gear but 3rd, the indicator is at 99 mpg (max) right down to 1000 rpm. In 3rd gear it drops from the 99 mpg reading at 2600 rpm.

Expecting a real hassle I took it to the dealer today. To my surprise, the mechanic noticed it right off; that is he felt it, with me driving. The mpg indicator was just added proof. Everyone agreed: very strange behavior. They couldn't find other such issues so we test drove two other 2011's with manual transmission. They both did it too!!! So now it's a case of "they all do that". I told them that I wanted answers, in particular, why, and can the behavior be changed by a hardware or software change. They told me it would take weeks to get those answers (and I'm willing to bet it's months, or perhaps never).

So, for you knowledgeable folks ... Does the behavior seem correct or even reasonable? It doesn't seem to be in the interest of my comfort, safety, driving pleasure, or peace of mind ... or in the interest of fuel economy and reduced emissions.

And, is there a way to get answers to technical questions (maybe even action) when one's dealership is not particularly keen on the issue.

- Vince

[xG35c]

Not sure exactly what you're describing, but I do know the ECU will cut the fuel off completely when coasting in gear down to some minimum RPM (usually about 2000) before activating the fuel injectors to prevent stalling. MPG will show 99 when coasting with no fuel, and the actual (lower) MPG when using fuel.

[SyracuseVince]

Originally Posted by xG35c

Not sure exactly what you're describing, but I do know the ECU will cut the fuel off completely when coasting in gear down to some minimum RPM (usually about 2000) before activating the fuel injectors to prevent stalling. MPG will show 99 when coasting with no fuel, and the actual (lower) MPG when using fuel.

That's what I'm talking about. In my car and the two others we tested it was 1000 rpm in all gears but 3rd and 2600 rpm in 3rd gear. And it's utterly reproducible.