Can Scan Guage improve my 55 MPG average

I've used this device for years and it hasn't improved my mileage at all. But I purchased it to be able to monitor info my Prius doesn't tell me, like RPM's and Coolant Temp.

 

At what temperature does your coolant run, where measured ,engine &/or inverter coolant. Types of trips? Thanks. :cheer2:

 

You're doing quite well, especially for NoVA. The ScanGauge may or may not help. It's not SG that will improve fuel economy, it's the driver. What it will do is help the driver optimize for efficiency

Study the threads linked from this one. They should give you some idea of what others use SG for and perhaps give you a better sense of how much it might help.

 

The Scangauge reads the coolant temp from the OBDII buss. There is an engine sensor that the computer reads and puts the data on the buss. I've seen the temp go from ambient to as high as 95C. The thermostat opens at about 85C, and in non-extreme ambient temps that is about where the coolant stays. But it will rise under heavy load (climbing a mountain pass), and will run much lower in very cold temps (last few days it was -20C and in the city, with both grills blocked, it took a long time to get the coolant up to 70C).

It currently only reads coolant temp. One day we -may- find the data to read out the inverter temp. but I'm not holding my breath. Note that it can read a lot of other data. Search on this site for a list (Scangauge codes).

If you're a worrier, don't get the Scangauge. It will tell you things that will make you worry.
If you're a tech. it will tell you useful things. Being a tech. you will know that you don't have to worry, just react when the data tells you to.

 

Probably not. I'm not sure which gen Prius you have, but if it's a 2G, then you are doing quite well. I'd say the SGII can get you from 45 to mid 50's but I don't think it can get you another 5%.

In any event, I have a PHEV modification, so I do find it very invaluable for optimization and monitoring of the plug in's performance.

They are fun, so get one anyway.

 

TY for the post, I'm an old tech, vacuum tubes to transistors. I never worry about anything. Especially cars. I used to DIY out of necessity, now it is curiosity. Back to Prius. What puzzles me, is, I can take a 40 mile trip, engine gets hot, I "assume" the thermostat opens, yet the temp at the radiator fill is 106 F. Ambient temp: 65-75F. On short runs the temp runs at 68F. No othe car runs in this fashion. I have studied the Bentley photo of the coolant sys, however no theory of operation is included. ???

 

The radiator fill point is -always- at a lower temperature than the engine. The thermostat is in the engine. Every car I have ever owned works this way.

The thermostat could be considered a temperature resistor. The coolant that is released to the radiator is at 85C or above, but as it travels in the hose to the radiator it rapidly cools. It cools even more rapidly in the radiator. Note that the higher the flow rate, the less the temperature will drop across the hose.

The Prius wastes so little heat that the flow is actually quite small, unless, of course you are driving at high speed across the desert at ambients of 30C or higher. So you will see much lower temperatures at the radiator fill point compared to the thermostat opening value.

There is so little heat generated that Pearl has trouble even getting to the thermostat opening temperature. Even after an hour of driving. In winter of course. In the summer with ambients of 20-30C it only takes 10 min to reach thermostat opening temps., but even then the thermostat probably doesn't open all the way. The only way I can get Pearl to exceed the 85C thermostat value is by grill blocking or climbing a very steep mountain pass.

 

Looks like you are right David, on every count. My 05 is operating pretty much as you described. That is probably why the thermos idea doesn't work, hot water never gets there. I was wondering if removing the thermostat would be beneficial or detrimental. It would result in a slower warmup, but may actually circulate to the thermos. I am speaking of finger burning temps. 120 to 150F maybe. Or might the car run even cooler?? I just bought a IR gun to monitor the temps and also did a full grill block. I did get slightly higher temps with a 20 min test drive, only 10-20F.

 

The thermos bottle does get hot coolant. The computer decides the opening and closing of various valves and pumps depending on the temperatures in various parts of the system. My ScanGauge clearly shows the coolant temp rise at each start up when the hot coolant is pumped into the engine. Hope this helps.

 

It shows me the HV battery amp during regen braking. HV battery can take more than I thought it can before the friction pads kick in. That's really good to know.

 

Yes it does, I don't suppose the actual temperature shows on the scanguage?

 

Mosty City driving, reaches around 190 degrees F during 70 degree F days. I assume the Scan Gauge is measuring engine coolant temps.

 

Not sure which "actual temperature" you were referring to. The ScanGauge shows the engine coolant temp reported by one of the Prius computers.

 

The hottest! Sorry for that, I would suppose that the scan guage would show engine coolant temps, altho the Prius inverter system would be equally or even more important. I guess I'll have to wait til next summer to really analyze the temps.