Dramatic improvement...(un)surprising reason.

[Bennett]

I've been able to beat the EPA since I got my 08 HCH-II despite crappy terrain. First week or so I was getting 45mpg into work, 35mpg back, then quickly upped to 50-55 in and 40 back for a first tank average of 45. Second tank 46, still improving, but as I got used to the feel of the car I got a nagging feeling.

Bumps felt kind of "gooshy" - I knew the feeling from my old Jeep when it got a slow puncture. Checked the pressures. 40psi. Drove a bit more, checked again. 40psi. Pushed on the tires with my fingers, peered at the profile. Just not convinced.

Got myself a new pump/gauge over the weekend. Checked with a third handheld gauge.

Both of the other gauges read 26psi.

FML

So yesterday I got all four wheels up to a REAL 40psi, and long story short I'm getting about an 8-10% improvement in mileage. The car just saaaiiillllls along now.

Now I'm just waiting for a good traffic day to get that elusive 60mpg inbound commute. If I was able to get a best-effort 58mpg on crappy tires then I'm hoping to kick a$$ with some overinflation

Lesson - double and triple check pressures.

Bennett

[worthywads]

Good diagnostic.

[RedylC94]

What type of gauge malfunctioned?

Once long ago, I traced the cause of a spell of better-than-normal mpg to a tire gauge that was off in the other direction. It was a plastic-bodied pencil-type one which had cracked, causing it to show less than actual pressure.

[Bennett]

Originally Posted by RedylC94

What type of gauge malfunctioned?

Once long ago, I traced the cause of a spell of better-than-normal mpg to a tire gauge that was off in the other direction. It was a plastic-bodied pencil-type one which had cracked, causing it to show less than actual pressure.

It was an electric pump, powered from the "cigarette lighter" socket so I can inflate on the road if need be. Checking with our other car the needle looks like it's a consistent 14psi off. It must have got banged up somewhere and the needle knocked out of alignment.

So long as I can guesstimate the real pressure, and I have a metal old-school manual gauge to double-check, it's all good.

[Kurz]

I love Dial Guages!
No Batteries, Pretty Robust, Easy to Read!

[Kurz]

http://www.amazon.com/Accu-Gage-Meis...892078&sr=1-25

This is the model I got.

[Bennett]

My battery pump was like that, only the needle was apparently "zeroed" at 14. Yeah.

[all_about_the_glide]

Keep going to max sidewall (at least) you'll be blown away at how she glides with the warmer temps coming.

[Bennett]

It seems fine at 40 - max sidewall is 44 so I may well push it up a little further. Tomorrow I'm planning on going in early - part work, part to beat the traffic and see what I can get...

[EdwinTheMagnificent]

Go, Bennett , go !

Kurz , I like your gauge. Seems a lot better than the battery-powered amazon gauge I have. What was I thinking ? I HATE disposable batteries ! I will order one of those along with my Kindle this weekend.