Warm up correctly?

I'm not sure what you're trying to achieve.

I have a Gen 2 (so, not a Gen 3 and not a Prius c). I have a ScanGaugeII : Linear Logic - Home of the ScanGauge and have used references like the 1st PDF at http://priuschat.com/forums/gen-ii-...angauge-best-threads-mileage-improvement.html. I do monitor IGN (ignition timing), FWT (Fahrenheit water temperature), RPM (ICE RPM) and bta (amps going in/out of the HV battery; this one's an XGauge. Prius c will almost certainly not be able to use any Gen 2 Prius XGauge values as the Gen 3 couldn't either.).

You can tell when you're still in stage 1a on the Gen 2 by the negative IGN values.

Personally, I wouldn't sit for that whole minute. Then, I wouldn't try to drive in EV only for 2 miles or whatever, because you've probably drained the HV battery a whole bunch doing that. That's probably why you're getting crap mileage while accelerating since a bunch of power has to be diverted to recharge the HV battery you just drained. Also, during that whole time the ICE is off, the ICE has cooled down a whole bunch. One can see this by monitoring FWT.

To quote from the 1st PDF:

The bolded part is important.

On the 2nd gen, one could achieve great mileage (<41 mph) by doing pulse and glide (Pulse and Glide plus Warp Stealth in the Prius II for maximum FE … - CleanMPG Forums). You basically want to pulse up to a certain speed w/the ICE and the glide by dead-banding (no arrows going in/out of anywhere) to prevent losses caused by either drawing from the battery or regening.

I believe that's how Wayne Gerdes (he runs cleanmpg.com) and company achieved Hybrid drivers complete run for mileage mark. Toyota.com : Hybrid Synergy View : 2005 : Fall : Prius Marathoners Top 100 mpg mentions it but there seem to be a few mistakes.

Don't take this dead-banding (no arrow) stuff as gopsel on the Prius c (since I've never seen one, let alone driven one), as it didn't really apply on Gen 3. The arrows on 2010-2011 Gen 3s were too small to see, it was (IIRC) to get no arrows anyway on Gen 3 and people instead use certain ranges on the HSI instead.

For you, I'd probably just go (don't sit and wait) and then find out what the proper pulse and glide technique is for the c to use during your low speed portion. And no, to answer http://priuschat.com/forums/prius-c...ase-accelerator-pedal-completely-gliding.html, releasing the accelerator completely is NOT gliding. There's regen going on (I can see it on the MFD in the form of arrows going to the battery and amps going into the HV battery on ScanGauge). You don't want that. You're incurring extra unnecessary (conversion) losses doing that.

 

Here's a link I bookmarked from some other thread. Covers off known programmable XGauge values. Hope this helps someone out there

https://docs.google.com/spreadsheet/ccc?key=0AiHL0r_2nhUEdF9lVVBxOVNoN3Zva3E0NmdZTUR1eVE&hl=en#gid=5

 

I wouldn't be surprised if none of those work on the Prius c. After all, none or virtually none of the ones from the Gen 2 Prius work on the Gen 3.

Fortunately, IGN, FWT, and RPM aren't XGauges and are reported by most cars. If the OP gets a http://www.scangauge.com/products/scangaugeii/ or something like the Torque app for Android w/an appropriate OBD2 dongle (I have no experience w/the latter), then he'll see what I'm talking about re: the IGN changes, ICE cooling off significantly when shutdown (via drop in FWT), etc.

Now that I think about it more, the ICE may have cooled off so much from the 2 miles of EV driving that it's back to trying to warm up again, consuming more fuel than when warmed up.

As as side note, I have very little opportunity in my drives to pulse and glide in my Gen 2 Prius but I've done it countless times.

 

They work In the C. I have programmed in about 10 of them with no issue.

 

By "they", you're referring to Gen 3 XGauges working in the c?

 

Yes...gen 3 codes work in the C...at least the ones I have tried so far.

-M

 

The one's I tried from the GenIII tab worked. Otherwise, why would I bother posting it?

 

I have a similar commute as yours except I have about a four block drive through a residential neighborhood and then hit a 45 mph boulevard before getting to the highway. I have found the best mpg for me is to just get in and drive slowly through the neighborhood, ~25 mph, not in EV mode though. By the time I get to the 45 mph zone the engine is usually warm enough and I can start to pulse and glide pretty quickly.

By the time I get to the highway the engine if fully warm and I can start gaining some lost mpg back.

 

minority opinion. just start it. drive it. dont floor it. forget about it

 

thanks, maverick. in the old days warming up was very important, but nowadays, in my opinion, just drive the darn thing. study how to get even better mileage. the car is going to do well as long as you dont abuse it.!

 

I figure if the motor is running to warm up, I might as well be driving with it. No real science to that thought, though, just what I decided. I'm also too impatient to sit there and do nothing, and don't usually leave my house until the last minute.

 

i agree with you completely, ashley. this is the 21st century. just drive it!!

 

Just my observations...

I have found it does not make sense to leave immediately in the morning (While in stage 1a warm up) since the car will only use the traction battery for propulsion at high discharge rates (even though the ICE is running). I wait a minute or two until the ICE transitions into Stage 1b (where the ICE can now charge and provide power)....This transition can be seen by monitoring the "AMP" xguage on my scangauge II..and there is a definite audible change in engine noise. Once that happens, I get moving without unnecessarily using up battery.

-M

 

If you monitor the xguage AMP, you can see the transition once the engine starts to charge the traction battery at a higher rate. It usually displays from -25 to -35 when stage 1b transition occurs versus below -10 in stage 1a.

I hope that makes sense.

-M

 

It is true on the Gen2 and Gen3.
It is not true on the Prius c.

Ken@Japan