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Prius electric mode only

Has anyone had success in installing the EV chip on the Prius which allows electric only mode up to 34 MPH ? No shop here in Scottsbluff, Nebraska will touch the job. It has colored pictures for the do it yourself guy and I’m a bit hesitant to tackle this in a hybrid car.

Any opinions ?

Let me guess: you want to use as little fuel as possible, right?

All I’ll say is that the car isn’t designed to use the battery in that manner, and you could well discharge it and wear it out long before it otherwise might fail on its own. Those batteries are not in any way cheap to replace.

I wouldn’t play with it.

I agree with Budd. Not a good idea IMO.

There was a post about this a few weeks ago. The trouble is that it doesn’t save any gas at all because even if your car’s running on the batteries, that electricity ultimately has to come from the gas engine and, as Budd says, the Prius’s computer is very good at deciding at what point that electricity will be generated most effectively. Also, the Prius’s electric-only range is not very far-- even at low speeds it’s about a half mile or so. The only way having the EV switch would be useful is if you have to move the car a few blocks, in which case you could do so without the cold start on the engine, so you could theoretically save some minuscule amount of fuel. But how often do you really only drive a few blocks?

There are companies out there that do a very involved and expensive conversion where they put in the EV switch, but also put in beefier batteries and a plug-in. Supposedly they claim this can extend the electric-only range to 20 miles or so, but real-world results seem very mixed.

Simple - possibly save a few cents, put $3000 batteries at risk. You tell me!

As I understand it the work is not difficult. Essentially you enter EV mode by shorting together two wires on one of the ECUs. But that sort of DIY is not for everyone.

This feature is enabled in Prius sold in many countries outside the US. It will allow you to proceed a very limited distance/speed on battery power. It will not ‘enable’ if you are outside certain parameter ranges. Apparently there is very little chance that you can damage Prius in this mode, but there are also major limitations. If you want to drive silently out of or into your garage in the middle of the night, it would be ideal…

As already mentioned the options for fuel saving are quite limited here. Higher tire pressures and combining short trips should be at the top of your list, if that’s the goal.