Poor MPG for hypermiling... Maybe it's my tires?

[Slopfrog]

Originally Posted by LeanBurn

What kind of tires do you have currently?

Thanks everyone.

They're Firestone affinity touring. 205/50R16s. And unfortunately they are new. Again, the sidewall is very much compressed even with them inflated to the maximum of 44 psig. I guess that's why they ride so nice... I've just ever seen a tire this way. I thought my gauge was broken,but I cross checked it.

I got an alignment on the car during the tank I got 25 mpg, and it was pretty bad. Which really means the increase I've seen with hypermiling driving style is even less! How many of my 5.6 mpg increase could be attributed to fixing the alignment? Hard to say, but definitely it's significant.

I'll have to get a gauge so I can find the optimum acceleration speed I suppose. There is the distinct possibility that I am spending too much time accelerating through 2nd and 3rd and their inefficiencies. I know the scangauge is popular, but the ultra gauge certainly is a more aesthetically pleasing product and at a lower price. That being said, there's gotta be something about the scangauge that makes it appealing to so many.

As for red lights, I sit in neutral. If the light is going to be awhile I shut the engine off.

I don't think brakes are hanging because I can coast quite easily on very slight inclines and the car is relatively easy to push.

Air filter is clean, not sure about plugs and wires. The engine runs great but there is 85k on the plugs.

[bestclimb]

Originally Posted by Slopfrog

Thanks everyone.

They're Firestone affinity touring. 205/50R16s. Again, the sidewall is very much compressed even with them inflated to the maximum of 44 psig. I guess that's why they ride so nice... I've just ever seen a tire this way. I thought my gauge was broken,but I cross checked it.

I got an alignment on the car during the tank I got 25 mpg, and it was pretty bad. Which really means the increase I've seen with hypermiling driving style is even less! How many of my 5.6 mpg increase could be attributed to the bad alignment? Hard to say, but definitely it's significant.

I'll have to get a gauge so I can find the optimum acceleration speed I suppose. There is the distinct possibility that I am spending too much time accelerating through 2nd and 3rd and their inefficiencies. I know the scangauge is popular, but the ultra gauge certainly is a more aesthetically pleasing product and at a lower price. That being said, there's gotta be something about the scangauge that makes it appealing to so many.

As for red lights, I sit in neutral. If the light is going to be awhile I shut the car off.

Scan gauge got to market sooner, they are made in the USA (I think) and there is some configuration that can be done to make it work with other sensors that are specific to some vehicles (Hybrids or diesels and the like).

I have the Ultra Gauge. Picked it for the price point, and the display. I would make the same choice again.

With an auto you can sometimes help by lifting off a bit, which can cause the transmission to shift up, then applying the most amount of throttle without it downshifting again. .

[LeanBurn]

I had those tires as OEM with my Corolla when I bought it new. They are bottom rung for nearly every category possible according to TireRack and my experience with them confirms this.

The good thing is that it can only get better from here. So wear them out and then get yourself a decent LRR type tire and enjoy quieter, smoother, better traction in all conditions and longer wear than what you currently have.

[roosterk0031]

You want to get into top gear as quick as possible, without going over somewhere between 2500-3000 rpm, probalby closer to 3000 maybe little more with your engine size. The reason's why this works, the engine is more efficent the wider the throttle is open but without reving too far. More important I think is going slow in 1st and 2nd you are only geting 10-15 mpg, so we need to get out of those gears quickly and last, with a auto we also need to get the torque convertor locked up.

With the Stratus 2.4 w/automatic I take it to almost 3000, let off to shift, and get on it again as hard as possible to hold that gear, repeat till hit target speed.

[GRU]

I acceleare quickly and let of the gas around 2500 to 3000 to shift, then back on the gas until i get to a desired speed...get a gauge and test your car at highway speeds....at a steady 60 mph, in warm weather you should be getting around 40mpg...if not, something is not right

[Slopfrog]

Well I've been trying to accelerate more aggressively and it seems to be paying off! I haven't completed the tank yet, but I have substantially more miles on the tank than when I filled up last time.

I am also trying to pay more attention to torque converter lockup. Getting it to lock up is not always easy. Sometimes it will lock at ~37 mph, other times it won't lock until 45. There doesn't seem to be a strong correlatin between throttle position and lockup either. Pretty sure last tank I was unlocked too much. You can definitely tell because if you give it a little gas and you're unlocked the revs go up out of proportion with speed, just like a slipping transmission would (which I guess is exactly what it's designed to do while unlocked.)

So thanks for the advice! It is also much more pleasant to drive this way! I can't wait for Santa to bring me an Ultragauge.

[2000neon]

Awesome It's always great to see positive results, and even better when it was free.

[roosterk0031]

Don't forget to take advantage of that speed on the coast, good acceleration and great coast is where the best gains are made (IMO).

[F8L]

Yes. Tires can make a big difference!

Tire Test Results : When Round and Black Becomes Lean and Green