Scangauge Accuracy

Hey Guys,

I find that the miles/gallons to empty is WAY off. I tried reseting and doing the setup all over a couple of times and always end up with the same problem.

Anybody here experience the same thing?? Is the Scangauge a reliable tool when it comes to calculating "to empty" data?

Thanks,

 

Did you set your tank capacity? Mine is very accurate

 

From what I've read and heard it takes a few fillups for it to actually start working. Dunno why its just what Ive heard. I dont use that gauge so I dont know if it works on mine.

 

Yes I did, 21.1 gallons right?

 

FYI your tank could have more or less than what the factory says. Think about the fuel lines and such will still have some fuel in them.

 

remember... garbage in = garbage out.

If it's not setup correctly, the data you collect could be wrong.

 

Sounds about right. K now go fill-up. The scanguage doesnt sense how many physical gallons you have in your tank, but instead calculated them by your mpg and how many miles you put on. It will work the best if you start out on a full tank.

 

Don't forget you engine size as well.

 

It wont have enough to make the scanguage completely off.

 

Do you stop putting gas when the pump stops the first time or do you give it a couple of extra go's to really top it off?

 

Honestly, the... .5 gallons you're gonna put in isnt going to make that much difference.

 

It depends...

When I first had mine put in (Dec 07), I was running around with 200lbs of sand in the bed and the scangauge was never accurate. In the spring when I removed the sandbags, it suddenly got really accurate and has been pretty dead-on ever since (no more sand bags in bed).

So - I'm gonna assume that anything out of the ordinary can affect the information it gives you. Remember, the scanguage is calculations based on the computer information and the information you set it up to.

I'm bone stock....with exhaust/air filter upgrades and when I fill it up (till pump stops) it's usually dead-on in gallons put in the tank or within .2.

I use the DTE (distance to empty) all the time and had it within 15 miles of empty and dead-on to the gallons I put in it. So - it CAN be pretty accurate.

 

So, does this mean that if you carry around weight (in my case, paint supplies and tools) it will not be accurate? It seems to me if the weight is basically the same during the whole tank, it should be accurate to this vehicle.

Or does the scangauge "read" the weight of the vehicle through the computer?
I am only on the second tank with my scangauge, and it is reading ....around... 18 to 19 mpg. Is that accurate? I guess I need another scangauge to tell me that!

GA

 

I don't use the "to empty" feature but I do reset the "fillup" setting each time I fill up. Mine is ALWAYS within .1 of a gallon and usually right on the money. Same station, same pump, let it shut itself off. So mine keeps up with my gas usage pretty darn closely.

 

My scanguage is pretty accurate in all aspects that I can check. I wouldn't think that the weight in the vehicle would make it incorrect, I thought it was calculating miles to empty by how many miles you have driven and gallons you have used up.
Just my .2 cents.

 

Weight isn't calculated at all. The truck doesn't have sensors to measure weight. I don't know the details on the exact data it uses or has access to on the OBD port. Mileage, speed, rpm's, etc. I'm going to guess it has no input on actual fuel usage from the computer or else it could better compensate for fuel usage when towing/hauling.

The winter gas mixtures has dropped my overall MPG's by like 2-3mpg although the scangauge is still pretty accurate. I always manually figure out my MPG's after every tank to compare.

If you're just plugging the scangauge in - give it some time. I think it actually 'learns' you & your truck over time based on previous data info it reads & calculates. I'm gonna bet by the spring time, it'll be working much better for you.

 

Mine is always right on the money or within .1 of being correct. That's pretty darn accurate for me.

HOWEVER to note.. when I pull my trailer then say I have 1/2 tank left then stop pulling and go back to regular driving. When I fill up in that situation it's WAY off. Only thing I can figure is that calculations are done over time and base on the GPH used each time you run your engine. The "extreme" difference between MPG when towing and when not towing (20mpg vs 10mpg) I think throws off the Scangauge. Just my observation though.

 

Its all in how you calibrate it. Go on the freeway and figure out if the mileage the scangauge reads is accurate to the mile posts. When you get it accurate by increasing the tire size percentage then do a few fill-ups and set it in the fill-up menu until its accurate that way. Mine is set to within 1% accuracy by setting it this way.

 

What 45longcolt said.

I don't know if you've been doing this or not but according to the manual, you're supposed to enter the number of gallons you fill the truck with on every fillup. If you don't, it can be wrong. The scangauge uses a fudge factor to recalculate your average and instantaneous mpg when you enter the actual number of gallons pumped. If it's indicating a higher average mpg than you're actually getting, it'll indicate that you can go farther than you actually can.

You can double-check the accuracy of your scangauge with the odometer and simple math. Reset your odometer and fill your truck. At your next fillup, divide the miles you travelled by the number of gallons you pumped at fillup. Preferably, fill at the same gas station and the same pump (to account for any lean when you last filled). This assumes that your tires are stock. If they're larger than stock, you'll have to adjust for that.

If you think you've got a setup problem, I found this on another site to reset your scangauge to the factory defaults. You would then need to go through and re-enter your data like you did when the gauge was new.

Press Red Button,
MORE,
MORE,
MORE
USE DEFAULTS
YES.