Average MPG goes down at stop? - Toyota Nation Forum : Toyota Car and Truck Forums

NMalvaux · 06-25-2009, 06:27 AM

I got into my 09 LE, cranked the engine, and before I started to move I checked my average MPG. As I sat there, the average MPG slowly started going down, approximately 0.1 mpg every 30 seconds or so. Has anyone experienced this? Why would this happen? I have been noticing that my average MPG seems lower later. Could this be a computer problem? Also, I noticed a tendency recently for the automatic transmission to be reluctant to shift to a higher gear as I lessen acceleration on a downslope. The car seems therefor not to let loose and coast as it should. Could this too be a computer problem, or a transmission problem (which I fear more)

buddy97 · 06-25-2009, 07:43 AM

Quote:

Originally Posted by NMalvaux

I got into my 09 LE, cranked the engine, and before I started to move I checked my average MPG. As I sat there, the average MPG slowly started going down, approximately 0.1 mpg every 30 seconds or so. Has anyone experienced this? Why would this happen? )

yes, the average mpg has to go down. you are sitting there getting 0 mpg.

***PhatRoyale*** · 06-25-2009, 10:00 AM

That's normal.

Think about it. It makes sense, doesn't it?

jdhog · 06-25-2009, 10:19 AM

You're joking right? Your burning gas but not moving anywhere, so how many miles to the gallon will you get when you're stationary? That's the reason some hypermilers turn off their engine at stop lights.

Regarding DFCO (decelleration fuel cut-off) I think some hypermilers tap the gas pedal sometimes to get it to shift, or they also put into Neutral to coast, but that is something you'd want to look more into to make sure it's safe.

sinnaever · 06-25-2009, 10:54 AM

No Comment...

I'll be nice... But ya its normal to get 0.0 MPG when stopping / stopped.

On the Canadian Models it actually goes by L/100km

And when we stop it reads "--.-"

But for Canadians (The rest of the Metric world as well), the lower the number the better. 5.0 L/100km is AMAZING... 33.5 L/100km is BAD

NMalvaux · 06-25-2009, 12:30 PM

Quote:

Originally Posted by PhatRoyale

That's normal.

Think about it. It makes sense, doesn't it?

Yeah, I guess it does, actually.

What about the transmission thing?

ernest t bass · 06-27-2009, 01:21 PM

"I noticed a tendency recently for the automatic transmission to be reluctant to shift to a higher gear as I lessen acceleration on a downslope. The car seems therefor not to let loose and coast as it should."

Sometimes my 09 corolla le will downshift itself when i apply the brakes on a downgrade. at around 45 mph or so.

this can be helpful or a pain in the ass.

When it downshifts itself to 3rd, you can manually select 3rd, then shift back to Drive and the trans will follow the command.

Restless_Surfer · 06-27-2009, 08:38 PM

When you guys fill up your tank to full....paid for it and everything and got in the car and press the button to check the range of your tank.

Initially, it was 604 km....now I'm only getting 540km at full tank...

LeanBurn · 06-28-2009, 03:46 PM

Actually if you let off the accelerator slightly it should allow it to shift to the next gear in an auto transmission as the load is decreased. Not sure why it would linger longer in the same gear on downslope de-accelerate situation.

I think it must calculate according to the last couple of fills, so if you have a short run and fill up at 3/4 full it factors that in as you haven't gone as far......so fill up consistantly at 1/4 tank and it will be more accurate.

The down shifting and DFCO is all in the name of fuel economy, which is its primary objective. I can cut cruise at 90km/hr and it reads 0.0L/100 kms until I get to around 35-40km/hr and then it bumps back into the 1.9-2.1 L/100km range. To put it into N while coasting would disable DFCO and you'd get increased consumption, while at stop some put into N to decrease load on transmission, and consequently engine, but it is a pretty small amount.

Last tank I filled up and the range said 789kms...and 5.0L/100km is pretty cool...

Restless_Surfer · 06-28-2009, 10:05 PM

5.0/100km........thats highway driving right?

Quote:

Originally Posted by LeanBurn

Actually if you let off the accelerator slightly it should allow it to shift to the next gear in an auto transmission as the load is decreased. Not sure why it would linger longer in the same gear on downslope de-accelerate situation.

I think it must calculate according to the last couple of fills, so if you have a short run and fill up at 3/4 full it factors that in as you haven't gone as far......so fill up consistantly at 1/4 tank and it will be more accurate.

The down shifting and DFCO is all in the name of fuel economy, which is its primary objective. I can cut cruise at 90km/hr and it reads 0.0L/100 kms until I get to around 35-40km/hr and then it bumps back into the 1.9-2.1 L/100km range. To put it into N while coasting would disable DFCO and you'd get increased consumption, while at stop some put into N to decrease load on transmission, and consequently engine, but it is a pretty small amount.

Last tank I filled up and the range said 789kms...and 5.0L/100km is pretty cool...

LeanBurn · 06-28-2009, 11:14 PM

I'd say 95% highway.