We have a 2009 TCH and quite frankly I have not been impressed with the fuel economy. It's ok, I guess, but around town it is a real chore to get maximum fuel efficiency. I find it very hard to believe that a **** 4 cylinder car can't get 30-35 mpg when running around at 45 mph. It seems that the needle wants to gravitate towards 25......

So I was curious if anyone know of a replacement computer chip or something that will make the electric motor run longer or at speeds above 40-42 mph. Something that would make the car a little more fuel efficient.....

 

Swap the TCH for a Prius, Volt, Tesla or Leaf.
Comparing the Camry to a typical 4 cylinder car might not be fair since this is a much heavier car. It takes more energy to push a Camry than a Corolla or other lighter car.
The modifications that you seek wont come free of charge. The cost of the chip or software upgrade might end up being a few hundred dollars, easily eating up any potential fuel savings. For example, assuming the life of the car to be 150,000 miles, improving from 40 to 42 average MPG will save 180 gallons, or about $500 (assuming gas <$3/gal) over the life of the vehicle. So, at best, unless you can modify the chip for free, the marginal savings would be immaterial.
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Now, what are the unintended consequences? Taxing the battery for longer stretches or for higher work loads (not an engineer, only guessing) might require more charge/discharge cycles and shorten the battery's useful life. Replacing the battery sooner (or at all) will blow any savings.
Now, at best, you'll only delay the ICE from starting for a limited duration, that being it wouldn't start at 40 but rather 45 MPH, for argument's sake.
The ICE is extremely efficient when powering the car at 40-45 MPH. The amount of gas used in this range is a tiny fraction of the gas needed to start the car from a stop or travel at lower speeds, so the amount of fuel savings might even be less than assumed above.
You're not eliminating the ICE, but rather just delaying it's start. The way I see it, the car typically travels within the following patterns...

• start up to under 20-40 for around town driving,
• 40-50 MPH while accelerating to highway speeds
• over 50 MPH on highway

If I were to guess, the average driver spends ninety percent of the time driving in either the first or third pattern, that is, around town or on the highway. Therefore the amount of time spent accelerating to highway speed is miniscule. I'll bet if you calculated how much time one spent in the 40-50 MPH range and then calculated how much the savings would be if you could tweak the engine to delay ICE for a few MPH, the lifetime fuel cost savings would be well under $100. For that, it's not worth the time, energy or risk to make the modification.

There is the also paradox of efficiency to consider. The driver who achieves greater MPG will probably drive more often, further or be less likely to car pool or combine trips since they're assuming that the high mileage they get they justifies the needless trips or inefficient car usage. If one wanted to use less fuel (not necessarily have a higher average MPG), there are far more efficient ways to use less. One could take public transportation (a bus with 50 passengers getting 6 MPG uses less fuel than a 50 Prius-es), car pool, avoid using the car unless absolutely necessary, find a job closer to home, move to an urban environment (NY, etc.) where there is no need for a private car, etc.

 

It takes away from your mpg if you're often accelerating to 45 mph. If you live in a city where the red lights are not far apart, that will hurt your gas mileage. If you are driving in heavy traffic in the evenings to go home from work that will sure lower you mpg.

The only thing I can come up with is to check to see if your tires are at 35 psi after they have cooled off. I wait to near dusk were no sunlight has been on them for a while, works best for me.

If you driving the TCH like a gas powered car, would give you about the mpg you are getting. Longer coast to red lights, softer acceleration helps. You might try driving 40 instead of 45 in town, if the traffic permits it. I found by using the cruise in town helps my mpg. If you in a hilly area, forget the cruise.

You can test you car by finding a flat older highway with little traffic. Drive at 40 mph and use the cruse. Watch to see if you mpg indicator reads 40 to 60 mpg. Possibly the ice will shut off and it should run in the EV mode for a ways. Another test you can do in the city when traffic is light. Drive at 26 to 30 mph and use the cruise control, preferably with the AC off, windows cracked. If your on a level street (no upgrade) you should see some rather high mpg on the indicator.

Wind can also lower your mpg if a headwind is 15 mph or faster.

Some buy any low priced gasoline, although I prefer a top-tier brand for a cleaner engine. Which weight oil are you using, a 0W-20 or 5W-20 oil and how many miles on your TCH..

 

Let me jump in here with a couple of thoughts...

First of all, the ICE/Electric switchover occurs at 42mph-indicated. On my car, and a few others I've heard of, the speedometer is always 3mph high, so 42-indicated = 39-actual. Cruising at or below 39mph is enough to attract incoming, hostile fire in some neighborhoods. So yeah, I wish we could cruise in electric mode to a higher speed.

Another thought is that we are just starting to see aftermarket upgrades for the TCH. For example, that add-on power pack someone posted in another recent thread. Now THAT'S cool! Drop the price by 80% and I'll buy one. But the product life cycle of these new aftermarket parts is still in its infancy. Give it a few years and someone will come up with a suitcase sized battery pack that can be installed and remove by he customer, at will.

One more... I travel a lot. During my trips I have noticed in many cities the taxi fleets are made up entirely of TCH and/or Prius. Boston's Logan Airport was running an all-TCH taxi fleet 3 years ago. Many local governments are also running TCH/Prius fleets as official vehicles.

Guess what? That puts them in the class of Crown Vic's and Tauruses (Taurii?) with regard to parts proliferation in the aftermarket and used market. And I used to work in auto aftermarket, from 1993-1998, as a corporate-level buyer, so I've seen this shake out before in a very detailed way. ALL new tech starts out this way. I can remember when FWD CVJ axles and Fuel Injection parts were astronomical in cost. Now you can get reman axles for $50/exchange and Injection parts are so cheap they come in as brand new parts out of China for cheaper than they can be rebuilt.

Be patient. By the time our cars hit 150k it should be relatively cheap to upfit them for another 150k, with potentially better performance.

Last thought on gasoline branding. I used to believe that "gas is gas" and that every brand probably comes from the same refinery, with the only difference being a chem-pack added at delivery to the branded filling station. That all makes logical sense. But a few months ago, someone posted, I think to this forum, the results of an informal study they did which showed Shell branded gasoline returning the highest average FE. My curiosity piqued and I decided to try and duplicate the study in my own vehicle. To my complete surprise, I also found that Shell gasoline was marginally superior to other brands. I also discovered that Arco branded gasoline was consistently, marginally worse than other brands.

I cannot reasonably explain the differences, but that was my observation. I've tried to stick with Shell for the past few months and my FE returns have been consistently better than before.

 

Some good info already here, and I'll add some comments based on my over 4 yrs of driving the TCH. Relatively minor changes in driving style can make big, big differences. Normal cars, if you try to take it easy and do the right things, maybe you can eek out 10% better FE. On this car, doing the same little things can get 20, 30 or even 40% improvement depending on conditions. But conversely, if you aren't doing the right little things, you are wasting 20, 30 or 40% potential better FE. On my typical commute, if I am a little impatient, rush to save a few minutes, and make sure I get to the red light before other cars to save my place (ie normal driving for most people), I'll see trip results of between 8 and 9 L/100k (not sure mpg, but mid first bar on the dash multi-function display). If I pay attention to FE, I can often push to full 3 bars which I think is well 40+ mpg and all it costs me is at most 5 extra minutes for my trip.

Any electronic mods to more heavily utilize battery power would have to focus on defeating the system's (albeit probably conservative) concern for making the traction battery last the life of the car. Running the car in EV above 42mph would require mechanical mods, because of the PSD setup (aka transmission or CVT) the engine must spin above 42mph to prevent overspin of the generator.

What are all the right things to do then? Difficult to define because it varies by person, experience and driving conditions. Some really basic advice though:

1) Although somewhat simplistic, consider that both pedals waste fuel, and the harder you generally push on either one the more fuel you are wasting. Coasting whenever practical makes a huge difference compared with regular cars.

2) It is possible to run 45 to 50mph at very low or no fuel usage, but you have to "ask" the car, not "tell" it. And the answer is not always going to be "yes". You have to learn a light touch on the gas pedal, and resist the urge to adjust pedal position for minor changes in incline. Be willing to give up 3 or 4mph on a slight rise or gain 3 or 4mph on a slight descent, try to keep the pedal in the same position. If the road isn't too hilly, and you maintain pedal position, often the car drive mode will transition into either:
a) fuel cut: the car will run on battery only, but the engine will still spin without burning fuel to prevent generator overspin
b) heretical: this is a funky condition where the electric motor creates an artificial load on the engine to force it into a more efficient state (an engine that is too lightly loaded is not efficient). You'll notice this when and with patience, again while cruising with a light and very steady touch on the pedal suddenly fuel consumption will drop in half via the gauge and, if you pay attention, the engine rpm will slow and a very, very slight rumble as the load is put on the engine.
3) If you can avoid stops without incurring too much extra distance (or by coasting or adjusting speed). Do it. Hauling a couple tons of car up to speed takes a LOT of energy, a lot more than a few extra minutes cruising around a slightly longer way and this is something that most people don't realize (until they have to get out and push their car).

 

Excellent post with good suggestions. However, I take issue with one point...
After having my '07 TCH for about a year, and getting pretty good at managing the pedals as you describe, I decided to see how good I could do on a whole tank of gas, just commuting to work (11 miles), and not letting other family members drive the TCH at all (little did they know how long it was going to take to empty a tankful!).

For that tank, I got 47 MPG, up from our normal 39 MPG (three drivers), and up from my normal of about 42 MPG. This is a 16% (+/-4%) improvement, using fairly aggressive (short of pissing off other drivers) hyper-milage techniques, given a not particularly great commute for maximizing MPGs.

Then (with little complaints from my family!), I decided to repeat the experiment with my '05 Siena minivan. One complete tank on the same daily commute using the same hyper-milage techniques (as best I could, given the inferior instrumentation, pedal sensitivities, and far greater weight). The van normally gets 17-19 MPG on the commute, but got over 25 MPG on that tank. This is a better than 30% improvement.

I think it would have been near impossible for me to learn the driving techniques that worked so well on the Sienna from the Sienna itself, since a lot of what I did was learned on the TCH (with great feedback), and then applied blindly on the Sienna (with a lack of direct feedback). Even though the Sienna has a instant MPG readout, it is hardly "instant" with about a 2 second delay, and is not easy to read (above the rearview mirror).

-- Alan

 

If you so much as touch anything that has to do with the hybrid system, and a Toyota dealer can prove it, you are leaving the door wide open for Toyota or your distributor to cancel your 8 year/100,000 mile warranty on the hybrid system.

 

Not true. There is a federal law re that issue. They have to prove that your mod caused the problem.
http://www.fuelsavings-greenemission...Statements.pdf

 

Guess again. They have the burden of proof to show where you caused the system to fail. This is no different than changing your own oil, rotating tires, etc.

I have no problem working on the system if it is required. So far it has not had an issue but I have changed the fluid in the "power split device" (AKA transmission) and will probably change the hybrid system water pump and coolant at the 100,000 mile mark.

 

All,

When I wrote that, I was responding to AlphaRat's original comment about an aftermarket chip to enhance the fuel economy of the hybrid.

And, I stand by that comment. If you install a chip or use an external non-Toyota programmer to modify the engine's performance, then it would be very easy for Toyota to prove your modifications meet the requirements of the 1975 Magnuson-Moss Warranty Act that they need to meet in order to invalidate or void your warranty.

Specifically, here are a couple of examples that would deal with the majority of aftermarket chips and programmers:

1. A chip or programmer designed to improve mileage: if the chip limits the amount or duration of fuel injected into the cylinder or alters the engine timing, the result could be a lean-burn condition, poor drivability, burnt valves, knocking, higher-than-normal exhaust temperatures leading to O2 sensor failure or catalytic converter failure. Tying the failure of any parts back to the lean-burn condition would easily invalidate your warranty, if it was caused by a non-Toyota part.

2. A chip or programmer designed to improve speed, performance, acceleration: If the chip extends the duration or the amount of fuel injected by increasing the fuel pressure or duration of the injection or the engine timing, the result could be valve coking, excess fuel readings in the upstream or downstream 02 sensors, excess wear on the catalytic converter or contamination of the intake manifold. It could also cause the car to fail emissions tests in states that require them. Once again, failed parts or parts that need excessive cleaning due to the chip or programmer and its' modifications would be easy to prove and ultimately invalidate the warranty if it was caused by a non-Toyota part.

3. Temporary chip or programmer use, then replacing the factory chip or program: some computers today (don't know about Toyota) can sense when a non-OEM chip or program is used in the car, and stores the data in the onboard module's memory. Once again, when the car is connected to a Toyota diagnostic scanner or device, the usage could be recorded, in terms of time, duration, and when it was disconnected or removed.

So, the bottom line is this: use Quaker State, Penzoil, Mobil 1, etc. etc., to do your oil, power steering or transmission service instead of Toyota-branded parts--no problem, as long as you used the proper fluid. Same goes for filters, wiper blades, etc. Use a non-Toyota device to alter or modify the computer controls or operation of the car's systems--BIG problem.

Joe