No, its not your friend. As noted below, the car already does this, and your mileage gain is from something else. Please see post #10 of this thread (bottom of page 1) as I get the impression you haven't read it yet.I disagree about throwing it into neutral. I have an automatic LTZ and I still throw my car into neutral when I know a stop is coming up. This has positively increased my mpg from 31mpg to 33mpg.
Also, I have a 2010 Cadillac CTS-V with a 6spd manual and operate the same way. That car sees gas mileage in the 21-24mpg range. That is very fair for a 550 rwhp / 533 rwtq car!! Throwing it into neutral is your friend!
:eusa_clap:You are doing yourself a disservice sir. Not only is this extremely dangerous, but your car already does this. Taken from a website:
"One additional feature new to the 6T40 automatic is an idle-neutral mode. When the vehicle comes to a stop, the transmission automatically goes into Neutral and then re-engages the gear when the brake is released."
If your doing that coming to a stop... your car also has deceleration fuel cut off, another feature already thought of. That is not the cause of your fuel mileage bump, sorry.
I have a bluetooth OBD2 adapter with which I can run Torque on my phone to tell me this information. I'll give it a try today when I get off of work and post the results tonight. I have a feeling they'll be the same as what the car is reporting on the DIC.Behavioral
Once your car is running in its optimal conditions and you're getting "decent" fuel economy, we can move on to some behavioral techniques.
A. Turn off your heater. In the winter, if its not unbearably cold, suck it up and leave the heater off till the car warms up. The reason for this is that the car will run in open loop until it reaches ~160 degrees F. During this time, the engine's PCM will ignore some of its sensors (including the MAF) and run rich until it has warmed up enough for the sensors to all be functioning correctly. If you run the heater while the car is dumping fuel to try to warm up, you're just prolonging the time during which it stays in open loop mode and wasting additional fuel. This is because the heater core essentially acts like a radiator through which you're forcing cold air. It may not sound like it, but it does make a significant difference. You can turn the heater back on once you've reached ~180 degrees F.
This question is for those of you with an additional mounted numeric graduated water temperature gauge-better than the OEM, or plug in diagnostic tool. From a cold start, for the 1.4L ECO engine, can you tell us what graduation marks on the OEM gauge does 160 Deg. F & 180 Deg. F equal(on the OEM, 4 marks is ¼ the way, 8 marks is ½ the way, etc..)?
Also, at full running temperature, my OEM gauge shows a hair width before the 7[SUP]th[/SUP] mark and stays there in any condition. What actual water temperature range is this?