2007 Low MPG -- Can't figure out why

Hi all,

I have been following the posts for the last few days, I just haven't had time to respond. Ok, so now I know that Techstream Lite and PriiDash are software and not hardware, that should help with the cost. It's too bad there are no iPad apps, it'd be nice to be able to plug my iPad into the data port and mount my iPad on the dash to monitor all of that information. I really was hoping to avoid reinstalling Windows on my MacBook Pro but from the sounds of things, that's what I'm going to have to do.

Do you think it would be worth it to give the dealership another shot? Is there any one in the Sac area who can recommend a different Toyota dealership that might be more helpful and can do something more than just a "health check?" What about the Bay Area? I'd hate to have to make the 2ish hour drive, but I will do it if there is a good dealership there.

If not, then I will pick up the software (I'm leaning towards PriiDash because Techstream Lite seems a bit overkill) and run some tests and report back here with my findings.

 

There are a couple people I know with a Gen II Prius. I think that, in order to get more meaningful results, we would have to basically drive the same route at the same speed at the same time with roughly the same load to get a better comparison. That way we can control for things like wind speed, temperature, speed, weight, etc. I realize that the issue is somewhat subjective (other than my photographic evidence of the behavior which is also somewhat subjective since you're taking my word for the conditions at which the pic was taken), but as sure as I am sitting here at my desk at work typing this out, I know that something is not right and that I am suffering a not insignificant mileage drop.

I think I might install Ubuntuu on my MacBook Pro and start with installing PriiDash (I read that there is an Ubuntuu version, unless folks think the Windows version is better). I'll take it on a trip where I can reproduce the issue and see what the gauges are showing (I'll try and do a screen capture also). If nothing shows up there, I'll give Techstream Lite a shot since that seems to go deeper.

 

I'll have to watch those videos another time, YouTube is blocked at work and I usually don't have time at home to do much of anything during the week. I'm off Friday so I might be able to watch it then. Incidentally, I'm not arguing that the screen doesn't come up at all. As I said, it's only the grapevine that I follow that screen. It's possible that in the past, it did that and I just didn't notice it.

I guess what I've been trying to say all along is that my Prius has been treating 7 bars as the new 6 bars. I'm not saying the problem is only on hills or the grapevine since, as I mentioned previously, I am having to refuel the Prius after 200 miles where as, driving the same speeds, I could refuel after about 380 miles, I'm just saying that is where it is the most pronounced. But if everyone is telling me that this is normal behavior, then I need to approach this from another angle and figure out what else could be hampering my mileage. Someone previously suggested putting the car on blocks and seeing if the tires freely spin. Maybe that is the next step.

 

You know, I was just looking at the preview pic to your first video where it shows the charging arrow and I couldn't help but notice that it was green. It's not green when mine does it. I don't think its part of the problem or anything, just an odd quirk I noticed. I don't think any of the charging arrows in my Prius are green. Maybe a difference between the 2004 and 2007?

 

Thanks for the heads up. If I do go that route, I'll be sure to buy or borrow the appropriate cable.

 

Interesting. A couple of questions, who did you take your car to? Was it a Toyota service department? Was your car behaving in a similar way to the way I had described in my previous posts (ie running at freeway speed with battery level in the green zone)? I'm assuming that you didn't have a "check engine light" (ie the computer wasn't throwing codes). Is that the case? Did they show you what the injector looked like? Too bad you didn't get a pic, I might be able to check my injectors and see if I have a bad or clogged injector.

It's possible this could be the source of my problems also, but I'm being cautious since I thought a new 12 V battery would fix it and it has not. I still will have the tires and brakes checked. I did confirm on my own that the tires are the right size and not too big. I thought that might be it when I noticed my speedometer is off by about 3 mph at freeway speeds (ie 75 is really 72, etc). The last time I had a car do that was because my Dad and I replaced the tires with bigger off-road tires (it was a truck).

Thanks for reporting back your problem. Hopefully I can report back my problem being solved soon.

 

Hi Ed,

Thanks for all of the useful bits of information. I'll definitely check out the coolant (since it is the easiest thing I can do at the moment). Given the way my car has been behaving, I can definitely see how the inverter running hotter than normal would cause problems. Don't know about cleaning the throttle body, that may be a bit outside my maintenance comfort zone. If it takes awhile, I also don't have a lot of time to spare. I have replaced the K&N with the factory air filter and like you, I never oiled the K&N on my previous cars .

As for the battery, you probably still have some time. My loaded voltage was at 11.6. I don't know how many miles you have now but at 12.2 V loaded, you can probably get away with another few months before you need to replace it.

Thanks again!