Scangauge II Fuel Economy Challenge

[GasSavers_maximilian]

I am trying to prove to myself a ScanGaugeII is worth buying.

To have a Scangauge II pay for itself in four years I'd need to attain a year long average of 43 mpg (assuming average fuel price remained the same). Does this seem reasonable to any of you? It's an experienced based question, unfortunately. I did own one for about two weeks and learned to drive with it on the roads that comprise 90% (or more) of my driving, but I'm sure I'd be more consistent with it in place. My estimated yearly rate will be around 39.9 mpg, so that's a 7.8% increase needed for payback.

Fuel prices could go higher, but this last year did include some very higher prices as well, with an average fuel price of $2.53.

So my questions are these:

1) How likely is it that I'm going to be able to suck another 7.8% improvement above my already pretty tuned driving habits? (I'm getting 37.5% over EPA with 45 psi tires and driving habits alone at the moment).
2) What is a good working estimate for average fuel prices in the next four years - likely lower bound and upper bound suggestions welcome


I guess there is another way of approaching this. What is the chance that I'd get one and sell it off on ebay and break even. Since they seem to retain their value quite well, it wouldn't have to save me much to satisfy this failure case scenario.

[Jay2TheRescue]

There's another possibility you haven't considered... Buy the Scangauge, use it for a month or 2 to tune your technique, then package it back in the box and sell it as nearly new... Several members here have done that. Now can you save enough to justify $25? Plus, you can always decide to keep it if you do decide that it gives you better information than the gauges. Personally I like to monitor the instant MPG and average MPG on mine... Most helpful to me.

[GasSavers_BEEF]

remember also that you can take the scangauge with you from car to car.

another aspect of the scangauge's value is the code reading. you have to drive quite a distance to "town" and if you needed to have a code read, you would have to go to advance or autozone which is unneeded expense in gas and you get the piece of mind of knowing what the code is earlier. most don't think about that unless their car is older.

I think that gas prices won't see a lot lower than they are. we have seen a spike but even at it's low point, we barely saw under $2/gallon.

you are also correct about the resale and that won't change. as long as it still functions properly, they usually bring a good $130 or so on ebay so you just have to get $40 worth of value out of it.

I hope to keep mine for quite some time after my car is gone. it is obd2 compatible. so it would work in pretty much any car (at least that I would get).

[GasSavers_maximilian]

Originally Posted by Jay2TheRescue

There's another possibility you haven't considered... Buy the Scangauge, use it for a month or 2 to tune your technique, then package it back in the box and sell it as nearly new...

I already did that. Only took two weeks to learn what I could. That's why I'm not positive I can justify owning one full time. My WAI requires me measuring IAT, and I was thinking that rather than buying a thermometer I don't really need, maybe I should reconsider the ScanGauge II as I never did run the numbers on keeping it (unfortunate oversight). I think the failure scenario clinches it: if it can't pay for itself I sell it off again. I never thought too much about code reading, only ever having had a code read once in all the time I've been driving. But it is still $40 a whack, so even once would tilt things considerably.

[GasSavers_maximilian]

JC Whitney has a 10% off promotion today with free shipping for things over $99, so I got one for $144. It'd be hard for me to lose selling it back off again if it doesn't pay. Wish I'd run the math previously, but what can you do? I think it's safe to assume that gas prices will at least stay at the current level, which is pretty much what it averaged over my year of keeping records. At that level it's a close call for the SG2 to cut it, but if prices rise I'm probably all set. I did have one tank at 46 mpg using it, but one isn't statistically significant. I have been assuming some other option will come along to replace the SG2 in the future, hence my four year repayment time frame.

[theholycow]

I don't think it can pay $160 for itself for you. You put enough thought, effort, research, and practice into saving gas that you're not going to be surprised by anything you learn from it.

• If you need a code reader, they can be had for $40 at Harbor Freight; I have one from there and it works great.
• With the way you like to tinker you could even have a realtime FE gauge using a cheap DIY project for far less.
• Your car has a long warranty and you seem to be very careful about not breaking it, so seeing extra gauge data isn't going to mean much for avoiding breaking stuff.
• The only extra gauge it could probably help with would be IAT for a WAI, but an $8 remote digital thermometer will do that job.
• If you wanted to see DFCO or air/fuel ratio, there are even cheap ways to see those, and even relative fuel rate.

It's a great unit. It's a wonderful luxury for anyone interested in saving gas or otherwise interested in technical stuff about modern cars. I recommend that you get one, you probably already know how you'd enjoy it from your past experience with it. However, it will not pay for itself.

I couldn't mathematically justify spending money on one either, but I was able to get it as a Christmas gift.

[GasSavers_maximilian]

Well if not, back on Ebay it goes!

That's a perfect gift: something you wanted but weren't willing to buy for yourself.

[GasSavers_BEEF]

there is also the gadget factor of it too.

you're an engineer. gadgets are cool. also the fact that data overload doesn't seem to affect the engineering types too bad.

I actually considered getting a second one and daisy chaining them together so that I could monitor 8 parameters instead of 4. there again, the cost keeps me from doing that.

dang all this cost justification

[GasSavers_maximilian]

Originally Posted by BEEF

you're an engineer. gadgets are cool. also the fact that data overload doesn't seem to affect the engineering types too bad.

I am slightly concerned that I won't be able to monitor that and also listen to podcasts. The ScanGauge won't win that fight!

[GasSavers_BEEF]

if your scangauge is audible, then something is seriously wrong with it. lol

a lot of guys with engineering backgrounds that tinker with cars have cars that look like space ships inside. I remeber a buddy telling me about a ford festiva that one of his friends had. put a v6 turbo in it. said the thing would glow at night from all the gauges. it would also smoke a set of tires off in a matter of minutes. he had very crazy friends.