Track your fuel economy and share with others your experience with the 2004-2009 Prius' MPG. Tue, 19 May 2026 01:01:19 +0000 Tue, 19 May 2026 01:01:19 +0000 PriusChat https://priuschat.com/forum/gen-2-prius-fuel-economy.21/ Mon, 11 May 2026 18:58:25 +0000 https://priuschat.com/threads/gen2-gas-mileage-mystery-better-going-over-hill-than-on-flat.259007/ https://priuschat.com/threads/gen2-gas-mileage-mystery-better-going-over-hill-than-on-flat.259007/ invalid@example.com (DashingDave) DashingDave
Puzzlingly (but not at all unwelcome) I consistently get better mileage reported (onscreen)
for the total Up and down (~54-55mpg) - than in the subsequent miles driven over the flat Central Valley toward Yosemite (roughly 51-52mpg).

Yes, I know I'm going varying speeds heading up and down.
On the looong downhill section I do get up to freeway speeds (~65-70),
versus maybe 40-ish going up...

Gen2 Gas Mileage Mystery - Better going over Hill than on Flat !?!]]> 4 Mon, 11 May 2026 12:47:03 +0000 https://priuschat.com/threads/i-beat-the-epa-post-em-here.1429/ https://priuschat.com/threads/i-beat-the-epa-post-em-here.1429/ invalid@example.com (efusco) efusco
FWIW,
This tank was achieved at temps averaging around 53 degrees F in mixed rural driving daily commutes of about 3 miles back and forth...

I Beat the EPA--Post 'em here]]> 720 Sun, 03 May 2026 15:46:30 +0000 https://priuschat.com/threads/fuel-economy-dropped-after-spark-plugs-replaced.176923/ https://priuschat.com/threads/fuel-economy-dropped-after-spark-plugs-replaced.176923/ invalid@example.com (1069FL) 1069FL Hello - In Jan. 2016, at 110,116 miles, I had the spark plugs replaced in my 2005 Prius at the local Toyota dealership. Right after, my mpg dropped from around 52 average to 47 average. Nothing else has changed. This average has been consistent for over a year now. I replaced the 12V battery in Jan. 2017 & I was hoping that would help but it didn't. I always keep the tires properly inflated. When I
asked the dealership about this, I got stonewalled. What could they have done or...

Fuel Economy dropped after spark plugs replaced]]> 32 Tue, 28 Apr 2026 11:28:43 +0000 https://priuschat.com/threads/500-miles-per-tank.255152/ https://priuschat.com/threads/500-miles-per-tank.255152/ invalid@example.com (Has Raf) Has Raf
View attachment 271940]]> 13 Tue, 28 Apr 2026 05:13:00 +0000 https://priuschat.com/threads/which-is-worse-ac-or-windows-down.50001/ https://priuschat.com/threads/which-is-worse-ac-or-windows-down.50001/ invalid@example.com (Mondrin) Mondrin 34 Sat, 10 Jan 2026 09:21:13 +0000 https://priuschat.com/threads/2005-prius-is-this-too-lean.258569/ https://priuschat.com/threads/2005-prius-is-this-too-lean.258569/ invalid@example.com (KitsuneVoss) KitsuneVoss This is fairly long distance, over 50 or so miles, including some highway.]]> 6 Mon, 15 Dec 2025 06:55:34 +0000 https://priuschat.com/threads/2008-prius-humming-when-driving-downhill.258156/ https://priuschat.com/threads/2008-prius-humming-when-driving-downhill.258156/ invalid@example.com (Illahee Rick) Illahee Rick
In Dec 2024 we replaced the hybrid battery with a Green Tech Auto pack with new cells (4 year warranty). During the summer of 2025 this noise appeared.

Seems...

2008 Prius Humming when driving downhill]]> 10 Sat, 01 Nov 2025 11:52:03 +0000 https://priuschat.com/threads/is-my-mpg-actually-bad-or-not.256423/ https://priuschat.com/threads/is-my-mpg-actually-bad-or-not.256423/ invalid@example.com (Prius92) Prius92
With about half city, half interstate driving, I'm only averaging 40-44mpg.

BUT, if I look here at Fuelly:

2008 Toyota Prius MPG - Actual MPG from 700 2008 Toyota Prius owners

The top 3 averages are 42, 43 and 44 mpg with the averages of all fill ups at 42.3 mpg.

I had Toyota check out the HV battery, which I rebuilt 2 years ago, it's not "factory new", but it's...

Is my MPG actually bad or not?]]> 17 Fri, 10 Oct 2025 17:40:32 +0000 https://priuschat.com/threads/g2prius-absolute-maximum-mpg-65-mph-and-beyond.257389/ https://priuschat.com/threads/g2prius-absolute-maximum-mpg-65-mph-and-beyond.257389/ invalid@example.com (cDxA) cDxA However, after finding out more about how the hybrid system works, I have given up on the idea.
According to A.I. , the Prius does not allow the car to take advantage of aerodynamic modifications to the degree that other cars do.
A.I. estimates a maximum of less than 60 mpg at 65 mph even with extreme aeromodding.

So...

G2Prius : Absolute maximum mpg @ 65 mph and beyond ?]]> 8 Mon, 06 Oct 2025 18:29:25 +0000 https://priuschat.com/threads/why-mileage-gets-worse-in-the-winter.99504/ https://priuschat.com/threads/why-mileage-gets-worse-in-the-winter.99504/ invalid@example.com (TonyPSchaefer) TonyPSchaefer
Why mileage gets worse in winter | PriusChat

Though this thread is in the GenIII forum, the discussion of winter fuel economy spans...

Why Mileage Gets Worse in the Winter]]> 72 Wed, 10 Sep 2025 12:50:41 +0000 https://priuschat.com/threads/most-efficient-speed-for-best-mpg.14675/ https://priuschat.com/threads/most-efficient-speed-for-best-mpg.14675/ invalid@example.com (Swamibob) Swamibob
Thanks,
Swamibob]]> 96 Mon, 28 Jul 2025 00:34:56 +0000 https://priuschat.com/threads/whats-the-price-of-fuel-where-you-are.255966/ https://priuschat.com/threads/whats-the-price-of-fuel-where-you-are.255966/ invalid@example.com (lexidium) lexidium
What is it in your neck of the woods?]]> 17 Tue, 01 Jul 2025 18:06:44 +0000 https://priuschat.com/threads/fuel-injectors-replacement-steps.255188/ https://priuschat.com/threads/fuel-injectors-replacement-steps.255188/ invalid@example.com (ColoradoCrow) ColoradoCrow After re reading it for the 3rd time I understand that the cylinder head cover is supposed to be removed.
But does it HAVE to be removed? The fuel rail will be in the way and the brake master cylinder (I HOPE) can just be moved out of the way and not disconnected from the brake system requiring a complete break bleed...

Fuel Injectors...replacement steps....]]> 17 Sat, 10 May 2025 18:37:44 +0000 https://priuschat.com/threads/17mpg-on-my-prius.254410/ https://priuschat.com/threads/17mpg-on-my-prius.254410/ invalid@example.com (Uwana) Uwana I noticed that when accelerating the car sounds like it struggling to cope. I've done alot of research and can't...

17mpg on my prius]]> 11 Thu, 08 May 2025 21:32:04 +0000 https://priuschat.com/threads/fuel-gauge-and-fuel-economy.253267/ https://priuschat.com/threads/fuel-gauge-and-fuel-economy.253267/ invalid@example.com (KitsuneVoss) KitsuneVoss
I checked the distance between the gas station I went to and home and it is 11.2 miles. My distance gauge that...

Fuel Gauge and Fuel Economy]]> 16 Sun, 23 Mar 2025 21:34:37 +0000 https://priuschat.com/threads/great-mpg.254409/ https://priuschat.com/threads/great-mpg.254409/ invalid@example.com (Has Raf) Has Raf
Now, I wonder if a diesel could beat this? A PD engine, without a dpf etc. before emissions rules were introduced? Or if an economical petrol-only ICE could beat this?]]> 2 Mon, 17 Mar 2025 02:01:45 +0000 https://priuschat.com/threads/fuel-consumption-indicator-not-valid.254302/ https://priuschat.com/threads/fuel-consumption-indicator-not-valid.254302/ invalid@example.com (Robert Drzewiczewski) Robert Drzewiczewski 3 Thu, 13 Mar 2025 18:02:14 +0000 https://priuschat.com/threads/low-mpg.253911/ https://priuschat.com/threads/low-mpg.253911/ invalid@example.com (Pacho1193) Pacho1193
Low mpg]]> 2 Tue, 11 Mar 2025 05:19:25 +0000 https://priuschat.com/threads/10-mpg-loss-solved.71920/ https://priuschat.com/threads/10-mpg-loss-solved.71920/ invalid@example.com (problemchild) problemchild
I was at the end of my rope until Saturday. I was walking the dog and my wife stayed in the car listening to the radio in aux mode. When I got back she...

10 mpg loss --->SOLVED!]]> 123 Wed, 26 Feb 2025 06:05:32 +0000 https://priuschat.com/threads/185-65r-15-firestone-weathergrip.253942/ https://priuschat.com/threads/185-65r-15-firestone-weathergrip.253942/ invalid@example.com (Brian Adcock) Brian Adcock
I recently purchased a set of Firestone Weather Grip tires. So far I am pleased with this set. They are rated snow/all season. My MPGs has only taken a 2/10s of a MPG hit.
I just wanted to pass along. I purchased from TireRack and very pleased so far.

Brian]]>