Less than 30MPG city driving! Why?

I live in San Juan, Puerto Rico. Average temperature is in the low 80s in winter. I drive about 50 miles/day mostly city and heavy traffic. I own a Prius 05 and average about 49 MPG. When driving on highways at 55 MPH I average 59 MPG, sometimes more.

The Prius uses both motors when it needs the extra power. Normally, when your start form 0 MPH and you gradually depress the accelerator the electric motor propels the car, then as speed builds up the internal compustion engine (ICE) kicks in and eventually the electric motor tuns off and stands-by for when needed.

After starting the car the ICE will run for about 5 minutes, this is normal. I use the Energy Monitor while driving at speeds below 42 MPH to use the electric motor and glide as much as possible and traffic allows. BTW, gliding is when none of the motors are being used to keep the car moving - much like coasting in a conventional manual transmission car with the motor off.

 

It could be because of short commutes. But, in my experience even then I get about 40-45 mpg when it is 60-70 F. Why don't you try this. With a new tank of gas (don't forget to hit the reset button) take a couple of 30 min drives in the city and see if you still get 30 mpg.

 

Well, I live in Ivine too, near Michaelson and Harvard, and my commute is 2 miles to work. My mileage has gone down, but it stays around 40-44, usually. On the weekends, we take the Prius everywhere we go, and that tends to perk my mileage up.

Also - I know it hasn't been TOO cold, but I keep my heat around 73-74, and that will KILL your mileage as well. I just installed an EBH yesterday, and I hope that will help me achieve a little higher mpg.

BTW - welcome to PC!

 

I live in Philadelphia and also get around 20 mpg _in_ the city. It's alot of driving one or two blocks and then hitting a traffic light, which I guess is pretty inefficient. It makes me wonder if they don't mean the lower-speed, suburban driving when they refer to 'city'. In the suburbs, with the speeds of 25-40 mph I get 50-60 mpg.

 

Mine dropped from 53 to 45 now that winter hit. Its the heater that is killing it. I tried turning it off in the city, but I prefer to be warm than to squeeze out a few more MPG.

 

Take a look at the EPA Detailed Test Information for descriptions of the various driving cycles used by the EPA to estimate vehicles' mileage.

 

Make certain that the parking brake is completely released.
Don't drive in "B".

 

Rexlee -

Practice the techniques. I get ~37 mpg, and my drives are worse from an efficiency standpoint than yours: cold weather, start at a low geographic point, never-ending big hills, multiple 5 minute trips. You'll surpass me in no time!

The Camry mileage seems about right - we used to get 28 mpg with our OLD camrys (92 & 96) when we drove our family (2 teen boys, a daughter, and a week's worth of baggage) to the eastern shore. Before he sold his 15 year old Camry this summer, my husband achieved a 400 mile tank with 40% Highway/60% City driving.

 

So what roads are you taking? Maybe I could help w/some alternate routing?

 

What does your wife's Camry get in the exact same commute as yours? I suspect, it'll be way lower than 23 mpg.

BTW, in your original post, you stated that Consumer Reports states 46 city/42 highway. That's not correct. See ConsumerReports.org - Most fuel-efficient cars where it says 35 city, 50 highway, 44 overall.

Regarding the EPA tests, see How Vehicles Are Tested and Fuel Economy Test Schedules for a brief overview of the procedure and schedule.

Have you also read http://priuschat.com/forums/fuel-economy/14701-new-owner-want-mpg-help-read-first.html? BTW, you mention "45 to 55 mph". Don't bother trying to pulse and glide at those speeds. The ICE has to run at >42 mph. Also, are you using auto on the climate control or have the temp above LO w/the fan on when you start out? If the latter, that can definitely keep the ICE running in order to generate heat when the engine isn't warmed up yet, wasting gas. If you press Off, you can see the ICE shutdown.

 

If you are following all advice from the gurus of this board, then there is no way you are getting the mileage you claim with a 2008 Prius. Even with my poor execution of following the advice of these folks, my 2008 gets 48-50 mpg in 40 degree weather. If I drive agressively instead, I still get 42-44 mpg. My daily commute is 10 miles so the engine takes the first 5 minute mpg hit too.

This is your first post here. Are you sure you are not a Honda hybrid salesman? Clever post if you are!

 

I am very amused by this. Your commute is 2 miles, temps are in the 50s and you have the heat on? It's been in the 30s here lately and I don't bother putting the heat on for my 4 mile commute. In fact last Friday night I drove to NY (5+ hours) and never had the heat on -- it was a balmy 54 degrees when I left and temps were in the 50s for most of the trip. I guess it all depends on what you're used to.

 

You guys up north have my admiration for your hardiness!

 

We have short trips also... in Honolulu. We got improvement when we started paying attention to the 5 stages of operation.

Originally we would just drive without a stop. We realized that if we took the car to a full stop after about 4 minutes and waited for the engine to go into stage 2... we saw improvement. Otherwise the engine would stay on longer reducing milage.

Our best discovery was when we realized that our Prius's (we have two of them) have mulitple personalities. One personality goes thru lots of changes (going thru the five stages) in the first 15 minutes. After 15 minutes the car warms up and STABALIZES. To us, it is a much better car with a stable personality.

Hope that helps.

aloha, richard

 

Well, I'm not sure how to take this, but I would assume in was in good humor. Though, I'd be a liar if I said that your post did not rub me the wrong way.

1. You assumed I'm running the heat in my 2 mile trips. Most of the time, I'm not. Did it occur that perhaps I run the heat on longer trips?
2. Cold is relative. I'm sorry you live in a "cold" area - but again, the term "cold" is relative.

Most of the times when it's been in the mid 50's I've had my windows down b/c the windows keep fogging up.

When I'm cold, I use the heat - that's what it's for. I'm willing to deal w/lower MPG's. As you know, in the Prius, heat is almost instantaneous, a pleasure that I enjoy.

As someone who has lived in Florida for 25 years, and SoCal for another year (their whole life equals 26 ) Yes, the 40's and 50's feel cold to me. If I lived in NY, maybe I'd run around in shorts and tshirt, but b/c of my conditioning (or lack thereof), jeans and a long sleeve suit me just fine.

Anyway - to the OP, if I get a chance this weekend, I'll see about driving your route. Do you wanna send me a google maps link, and I'll take a crack at it?

You can PM me this if you want. Also - I'll be in Long Beach until Friday, so you may not hear a reply from me until then.

 

Is this the route you are talking about? from:Irvine Center Dr & Jeffrey Rd, Irvine, Orange, California, United States to:33.663211,-117.706661 to:Bake Pkwy & Dimension Dr, Lake Forest, Orange, California 92630, United States - Google Maps

Can you describe your speeds/driving style on these roads?