Hi,
Glenn in Iowa has a broken Prius and needed a diagnostic scanner. Ordinarily, I would rent out one of my Graham miniscanners but they were both out. So I sold him my ScanGauge II that had been upgraded to V4.05, a pig-tail to avoid 'spiking' the Ts/Tc line (pin 15), and pre-programmed for traction battery analysis. His last repair action was a traction battery swap. But that left me w/o a ScanGauge.
I ordered from Ecomodder and just received my replacement and I am happy to report it has the 'new manuals.' I haven't fired it up yet but having the new manuals means it is at least V4.02 and possibly V4.05. Regardless, I'm one very pleased customer.
Let me share which metrics I use for efficient driving:
- ICE coolant - NHW11 Prius warm-up is centered around 70C. Until the car reaches 70C, it can not go into 'hybrid mode' where the engine is off. During the warm-up, it is important to minimize engine load so I frequently shift into "N" to coast with the engine at minimum fuel burn. Up until ~50C, at a stop light, I can mash the brake, shift into "R", and touch the accelerator and the engine will stop and stay that way by shifting into "N." This avoids fuel burn at a stop light or long stop sign while it is warming up.
- ICE rpm - based upon BSFC metrics, up to 2,400-2,600 rpm is good. Anything over that starts to burn more fuel per unit of power. Above 3,200 rpm, it gets really greedy. As for above 4,150 rpm, you only see that in maximum and very fuelish operation. The 1.5L engine has to enrich the mixture at higher power settings to avoid burning out the catalytic converter.
- gm/sec or Gal/hr - either one is a measure of fuel flow. During the first 45-55 seconds, the NHW11 will keep the engine in a fixed, idle mode and draw on traction battery power to accelerate. Monitoring the fuel flow rate is key to staying in this modified EV mode. But once having reached 35-40 mph, easily done, the MPG will exceed 50 MPG and if one shifts into "N", exceed 100 MPG. The rest of the warm-up not so nice but shifing into "N" works quite nicely until the coolant reaches 70C.
- 4th - any experimental data. Only three are really needed for efficient driving of the NHW11 Prius.
Well I must run off to another meeting but wanted to share my thanks to the Ecomodder team and this great price for a ScanGauge II.
Bob Wilson