Hi all - I had entered a more verbose post - but it didn't post. Short form: I hear a motor/compressor running once or twice after I had put a 40# box into the trunk. I had opened the driver's door - but NOT turn the vehicle on. This doesn't sound like the evaporative sound described in the manual. If I had to guess, I would say it was a compressor for a load-leveling system or "air shocks". I couldn't find any reference to such a system on this car in the manual. That would fit with the box in the trunk situation. The vehicle has been parked overnight, for at least 12 hours, so it also doesn't fit the description of the sound the vehicle may make "about 5 hours after use" from the evaporative system. Ideas? I promise to come back and properly introduce myself, I just wanted to get this out there right away. I did search the newbie forum for this, but didn't see anything that sounded like it.
Kind of rattlesnake-y pump sound under the hood when you open the driver's door is the pump pressurizing the brake system to be ready for use in case you start the car.
Hi Ray, I may have - but I think I heard it twice - once before I opened the driver's door, and once after but before getting in. After having the vehicle a few more days (and loving it) I'd venture a guess that it has something to do with the brakes. The owners manual alone - even though I've been devoutly reading that 800-page tome - doesn't describe the systems very well. Based on my past experiences with the old GM diesel cars (early 80's) having an engine-driven vacuum pump to operate the power brake vacuum booster - I might guess the Prius has an electric vacuum pump to run the brake booster when you're in EV mode. Did I guess right?
I think that's it Ray. While I have you here - where can I find an in-depth technical description of this vehicle's systems? The owners manual doesn't really get that into it, and I don't think I'm ready to pay the $$$ to get the manual off of TIS....
I don't think the $20 for TIS is all that $$$ for what you can get, but still, Elektroingenieur did put together a whole wiki page with various ways of getting the information, some of which may be free depending on your access to libraries, etc. However you get there, the volume called the New Car Features manual is the one that gives you the best "in-depth technical description of this vehicle's systems". The Repair Manual, also there, more or less assumes you've seen the descriptions in the NCF; it's kind of a jump in the deep end if you haven't.
I guess what I meant was that the $20 for two-day access is expensive unless you can practically download, save, and index a bunch of information in those two days. (Read somewhere here on this site that that wasn't a practical approach.) Also seems that if you could do that, then TIS wouldn't be able to sell any of the more expensive access packages. I did also read that a Chilton library was available online. I'll have to see if our local library subscribed to that. Being an "older mechanic", I'm still comparing available aftermarket service information to the old "Motor" and Chilton manuals that could be obtained for a reasonable fee and we're pretty good. Bought a Haynes manual for my 2000 Ranger and it just doesn't measure up. As a Buick mechanic I had the luxury of a full set of new factory manuals every year. Even then any owner could buy that whole set for about $100. What I REALLY miss is GM Factory Training where guys who work on these cars every day would teach you the new systems and the little "tricks" to keeping them running. I'll check out that Wiki that Elektro put together.
I used Chilton and Clymer books on my first car. Nothing like the joy of figuring out entire systems I would find in the car that the book never even mentioned. I haven't looked back since I started using factory docs. Whether $20 for two-day access is expensive I guess depends on what you compare it to. I bought my Gen 1 manual set on paper and spent over $200. The set for a friend's Volvo was over $1200. (Volvo made a separate "volume" out of every what Toyota would make a "section", and was pricing those "volumes" at $10, $20, $30 each.) I regularly watch people on PriusChat spend three and four figures on parts to swap out, to avoid the expensive $20 where they could find out how to diagnose their car problem. I occasionally sign back in to TIS and feed them another $20 when I've saved up enough questions I'd like the answers to. Some years that's never, some years I might do it twice. My cost has probably averaged about $9 a year that way.
