OK, I plan to fix a fuel valve problem next week, but I am disappointed with the mileage I get in this high mileage prius, it now has 325,000 km (former taxi) and I'm averaging 8 L/100 km in the city. I was expecting to drive electric most of the time in town. What's wrong? Is it just the high mileage the car has?? The engine comes on quickly after IG-ON/brake. Is that normal? Does it mean my batteries need replacing?? Nothing more?

 

My guess would be your fuel valve problem, unless your battery pack wasn't replaced somewhere around the 100,000mi mark. I am not sure how to translate this into metric for you, but after ~40,000 miles and six years on my 2004 Prius II, I am averaging ~42mpg. The engine will come on quite often, unless you are roving around town at a speed under ~25mph. Then you might run on the battery for up to a mile. The motor will be on quiet often in city driving, charging up the battery. Once the fuel valve issue is fixed, I would be surprised if your efficiency doesn't climb.

 

Hey, Agamotto
many thanks for your feedback. Tomorrow's the day for the valve and i hope that does it. Mileage much better already, i think my mistake was using 'b' for driving in town. i use 'd' now and can coast more, charging the batteries nicely and even travelled almost 2km/over 1mi on full electric. Good to know about the speed limit for e-drive. i've only read about ford escape up to 50km for e-drive. Anxious to see what happens after today.

 

The 'b' setting on the transmission is for engine 'b'raking. It leaves the engine engaged to slow the car without overheating the brakes, when going down-hill. It is intended for use only on long, steep down-hill roads, such as large mountains.

 

Yes, it seems the garage was incorrect in telling to use 'b' for town travel. I thought he might be right because I was hoping 'b' would charge batteries faster since car had been sitting for while, but no need. They seem to re-charge really fast. I get 'green' reading in no time, but only get up to 6 bars, not all seven, ever. They seem to hold the charge for a while.
Do the charging bars represent battery cells? or just an indicator of charge? One bar missing = one cell dead?
How do you tell if cells need replacing? Can't find that in manual.

 

Don't worry about that top green bar. The last bit of capacity at the top is reserved to take some energy from the brakes. The car will almost never fill it full, except when you happen to use the brakes while it is almost full.

The charge state will go up and down many times each day. Just accelerate gently and brake gently, and let the computer figure out how to best use the battery.

 

Trying to stay in electric only is NOT necessarily the most effiicient way to drive it. The energy has to come from somewhere. You're incurring a whole bunch of losses such as from having to run the ICE to generate it, converting that rotational energy into electricity, resistance in the wiring and battery and reconverting that energy into rotational energy.

Basically, don't do it unless you're doing pulse and glide.

I like the quote in one PDF at http://priuschat.com/forums/gen-ii-p...rovement.html: "I refer to this as the Hybrid Paradox: You bought the car for the economy of the battery, but must minimize use of the battery for optimal ecomomy."

It's not a a great indicator of charge because it's not a 0 to 100% indicator. See http://privatenrg.com/#Full_SOC. I can confirm that via ScanGauge that all bars filled == 80% or a bit higher. The car starts doing funky things if you hit 80% SOC (presumably to keep the battery from going much over 80%) and are coasting down a hill. You'll actually see no regen occuring (by monitoring BTA) and actually a draw coming out of the battery + the ICE's RPMs going way up (to say 3000+ RPM) instead of being at say ~1000 RPM.

+1 esp. on braking gently. Before I bought ScanGauge, I thought I was being very gentle on the brakes already. But when monitoring BTA values, it seems I wasn't. It's easy to trigger 90+ amps of regen even on what seems like gentle braking. Too high an amperage should result in a lot of losses (as heat) due to resistance.

 

I've replaced two components related to the fuel valve, including the fuel valve and I think I now have a true Prius II.
It drives great, switches off at lights like it should, starts immediately upon acceleration without extreme mpg usage and allows me to glide, ie. pulse/glide, as I have read on many an occasion. Now I hope the >300k km mileage will actually prove to be irrelevant for the prius and I get another 300k out of the engine. I'm watching the engine oil closely.
Thanks to all for your feedback and the very detailed last response. Great pics and tech support on the prius. Thanks!!

 

A little side note, in 'B' drive some energy is wasted that can otherwise be gained while in 'd' drive since the wheels also have to spin the engine as an air compressor (no fuel is actually used until you actually press down on the peddle). However, it's still good to use 'b' while going a long way downhill. I've used it plenty of times in the colorado rockies.

 

We own a 2008 Prius Touring Model and get an average of 42-45 MPG consistantly!