Poor Gas Milage

I got my new 2013 Prius just a year ago and I have never got more than 36-38 mpg, except on a highway trip, where I actually got almost 50 mpg. I thought the Prius was supposed to get better mileage with city driving, but evidently not. However, I also live less than 5 min from my office and have two stoplights in between, so it's always stop and go. I gather that's the reason, but it doesn't help my attitude toward the new car. I had a 2006 Prius before and got at least 40-45 on the same trip. I'm really disappointed in the mpg.

 

Yes. Ride a bike to work.

 

You could try letting it warm up in your driveway before taking on the hill with a cold engine. It maybe better than what you have been getting? Be really light on the throttle as well. You can do this provided your not holding up the trafic. Good luck as this is a difficult one. H

 

Change jobs again.
Honestly, you don't realize that your driving conditions are the total cause of the change ??
Well they ARE.......and the answer probably is NO.

But consider this......even when you were getting 48 overall, you still were getting just 36 during the first 5 minutes of your trips.

 

Cold engine, short distance and uphill all spell lower mpg. Am curious how big the hill is and what the mpg is on the return trip? I got a low of 39 mpg with rather large hills and 65 mph over 290 miles with 75 of that being relatively straight, even downhill slightly. That means the uphill part dipped as low as 29 on the CONS display. In my experience, the Prius does not do especially well on short trips unless the ICE is warm and able to shut off for much of it.

 

you might try driving in the opposite direction and taking a circuitous route, arrive at work from the backside. that should greatly improve your mpg's. i assume you do much better on the downhill trip home?

 

The MPG ratings assume specific trip profiles, which perfectly match essentially nobody's real life trips. The city profile tests starts with a warm engine, and runs more than 22 minutes. Your much shorter cold engine commutes don't stand a chance.

On top of that, the official ratings are not the same numbers produced by the tests, but are discounted by empirical fudge factors, meant to compensate for what real drivers typically got in real life at some point in the past. But because 'real driving' is a moving target as people continue to buy more powerful cars, drive faster, accelerate harder, and drive more aggressively, the fudge factors are always out of date.

But the city and highway ratings have different fudge factors, intended for typical old fashioned non-hybrids. Because of that, the 'fact' that Prius has a higher City rating than Hiway rating is really just a meaningless artifact of an artificial scoring system intend for a different type of car. On the original tests results before those fudge factor discounts, Prius produced nearly identical city and highway numbers. But your results will depend on a lot of additional factors that just cannot be rolled into the scoring system.

But look on the other side. Your very short commute will roll up very few total annual miles, so your commute fuel consumption will also be very low, much lower than with any regular non-hybrid. The only effective ways to reduce that would be to use some other transportation that doesn't require you to warm up a cold combustion engine -- walk, bike, take a bus, or use a plug-in vehicle.

I will go out on a limb and suggest that your 2013 gets lower commute MPG than your 2006 because the newer car has a 'new improved' system to warm up the engine coolant faster. Neither car will fully warm on your short commute. But the new one gets closer, costing more fuel. If your commute was long enough for both cars to fully warm up, then the 2013 would beat the 2006.

 

Sanity Check: Are you using less gas? If yes, why do you care that the MPG is lower? I drive 50 miles each way most days, which is good for MPG but it is a lot of gas. I would never get as good an MPG on short trips, but I would use less gas.

 

This. While your MPGs are lower, your actual gas consumption is likely much lower.

As for getting better mileage, Jonny Zero's suggestion of biking (or even walking) your commute and saving the car for longer trips would be the easiest way to both raise your MPG and reduce your overall gas use.

 

You got the wrong prius. The one you wanted was the plug in version. Sounds like you wouldn't use a drop of gas on your round trip commute. That being said, you are in a pickle, short trips, uphill while the engine is warming up is not good for MPG's. Still, you are getting better than what most cars "advertise" as their superior Highway MPG. They'd get 12 - 15 mpg with your commute.

 

If you have a Scangauge or miniVCI, run a series of warm-up tests over a week, five samples:

• Cold-start and drive - get ready to drive, with foot-off-brake, push start and reset test trip meter, then start car and drive the same way, each morning, record ending MPG. You'll need five samples, toss the lowest and highest and average the middle three.
• Warm-up to closed loop and drive - same as before but monitoring the fuel trim, wait for closed loop operation, about 45-55 seconds. Once closed loop begins, drive and again get five samples.
• Warm-up to first engine stop, ~40C, heater and A/C off - same as above but waiting for the first auto-stop. Then drive, using heater and A/C is OK once driving starts.

After three weeks, you'll have metrics and know which approach works with your particular route. If you have a GPS that can interact with Google Map, share the altitude profile of your route. We don't need to actual route but a clue as to the altitude changes.

Bob Wilson

 

Chop, for next to nothing you can block your grill. I don't know if it will make a significant difference on your trip but it may be measurable.

 

It is NOT a good idea to completely block the grill ........ever, on any vehicle even in below 0F weather.
Ever notice the little triangle opening in the middle of the grill blocks on big trucks ??
After the engine gets fully heated up, it NEEDS some air flow to prevent overheating.

 

Also, you have two radiators, Engine and Inverter, it is easy to find engine water temperature on the ODBII bus (FWT) but some models do not report inverter water temperature, so if you block the inverter radiator, you are flying blind.

 

Inverter & engine coolant temperatures do not get excessive, especially in 5 minutes. ICE coolant doesn't reach 200F. Inverter temp is all over the place depending on the type of driving. I seriously doubt my inverter gets any warmer than one in Florida in the summer.

The difference between Outside Air Temp is greater than +20F. If it is safe to run the car in 90F weather when the inverter is 110F then I will almost guarantee that an inverter behind a blocked grill in Ohio in the fall and winter isn't going to reach 110F.

There's no excuse for flying blind. xGauges are available on the ScanGauge.

 

2012 Prius III
I used to live in Dallas, and I had some fuel economy tires. The MPG was great close to 50 MPG. Though, I don't know if the tires help but I would not recommend those tires again as they wore out quickly. I moved and my commute to work was cut from 18miles to 9 miles. Still the same amount highway driving, MPG went to 38. At about the same time I got new regular all season tires and a new 12Volt battery. I made the drive from Dallas to Seattle with car full of stuff the MPG stayed around 38. Now I drive maybe 1 mile to 5 miles when I do drive in Seattle. I am getting about 36MPG. The service adviser said it is normal.

 

sounds about right. you could try changing tires, but the fuel savings probably wouldn't make it worthwhile.
what tyres pressure are you running? how many miles on her?