Mike85220

I noticed a few days ago that out of the blue, my Economy gauge started climbing and diving radically.

Literally I would press the gas and the numbers went down, and when I let go of the gas, or braked, it went up.

I had to reset it, and it seems fine now.

But I have to ask... is that normal or what could have sparked this?

I have not reset the Economy in 10k miles. I doubt it is a factor, just throwing that out.

TommyP

iTrader: (2)

Are you sure you weren't just on "instant MPG"?

scottydoh

Yea, no offense, but a little common sense here... if your on instant, when your on the gas, your mpg will go way down, 0 if your sitting still, but if your coasting down a hill or such, it will to way up...Ive seen mine go up to 99. Also recently I read some where on here that when idling over 1500 rpm, the computer shuts down the injectors to save gas.

Mike85220

I guess my description was vague.


I mean in it literall would drop .8 MPG within a second, the numbers would shoot down.
This would happend with 1/3 the pedal down, and vice versa.

The gauge was going nuts, not normal.

Normal is the MPG goes up .1 if I am at 70 even for 10 miles.
Not it keeps dropping just because I barely get on the gas.
Not it goes up a whole MPG just because I decellerated down an off ramp.

scottydoh

But you still didn't include if your looking at average or instant

TommyP

iTrader: (2)

he has to mean the average because the instant doesn't do tenths.

DaBuzzard

^^^^ true that

I have noticed some weird **** with mine on instant - cruising at 55-60 mph, showing 36-37 on the dic, all the sudden it starts climbing, sometimes to as high as 85-90 mpg (I wish) then drops in a flash to 8-9 and climbs back up to 36-37. No change in speed or throttle opening, just some strange glitch.

I could see this causing the average to change more quickly than it would be expected to normally.

What causes it? Damned if I know

Mike85220

That is what I mean, mine usually goes up and down a tenth of a mile per gallon here and there if I cruise at a constant speed or perhaps gun it to pass someone.

But what happened here is massive fluctuations from the slightest driving differences.

So you are saying there is two meters? An instant and average? Maybe I selected the instant somehow? Or is there an instant?

TommyP

iTrader: (2)

for you, IDK, which trim level and year your car is it. My 08 SS/TC has it, but idk if the lower models of the same year or newer have them. I know the lower models on the 07 and down don't.

fshizl

iTrader: (1)

the instant gauge is after teh average gauge...

it goes odo... trip a , trip b, miles remaining on tank, average mpg, instant mpg, avg speed, oil life, temp, tire pressure front, tire pressure rear...

dont quote me if i am wrong... i did this off the top of my head lol.

DaBuzzard

afaik, 07 and earlier did NOT have inst mileage on the dic, 08 and later did.

Mike85220

Mine is an 07 LS, and I am wondering if it goes to instant if you click the reset button once quickly.

Holding it down for 3 seconds resets it. Maybe I hit it by accident.
Could be wrong, but it acted as if it was an instant fuel check.

scottydoh

Its pretty obvious if your on average it says "AVG MPG ---" if your on instant it says "INSTANT --"

Mike85220

Mine says ECON 31.3 MPG... thats it

scottydoh

hmmm, well i have an 08 LT...I guess they changes the system some were in between

Nighthawk243

ECON indicates the old system... which is an average. The only way it drastically changes very fast is if you just recently reset it.