Mileage Drop after Dealer Service

I haven't had this problem but I think that one problem some people have is that the dealer puts in 4 quarts of oil instead of 3.5 quarts. Have you checked that?

 

Definitely check the tire pressure - put it up to 40/42 or even a little higher to prevent uneven wear and to promote better mileage.

As for getting it back... What are the temperatures like there? It's damn cold here... and thats hurting mileage (by a lot), as is the use of winter blend gasoline. Add to that the need to run the heater (which makes you run the ICE more to provide the heat), and you're talking about a noticeable chunk of your MPG going during the winter months. Do what you can now, but i suspect you won't see much, if anything, until it warms up.

 

<div class='quotetop'>QUOTE(dgarbely @ Dec 4 2006, 01:25 PM) [snapback]357579[/snapback]</div>

If correcting the tire pressure did not cure the problem, my suspicion the oil viscosity is to blame. Another poster recently experienced a similar drop in MPG after he had his car serviced at Jiffy Lube. After replacing the heavier weight oil with the correct viscosity, his mileage went back to normal.

Sudden, significant drop in MPG after an oil change

 

When I had my 5000 mile service, the dealer adjusted the tire pressure back to what the manual says, which is lower than the 42/40 that I'd been running. I've heard that this is normal with the dealer service, so I checked and adjusted my pressure the next morning.

 

<div class='quotetop'>QUOTE(dgarbely @ Dec 4 2006, 03:09 PM) [snapback]357640[/snapback]</div>

I think so, but my car, with the manual, is in an underground garage some dozen floors away.

 

history: 05 original owner has 24500 miles normal 50+MPG warm weather lately 48MPG. Never had a problem. TILL NOW!

I ran my Prius out of gas (Short ver. unresolved fuel gauge issue) 1/2 miles from gas and dealer (talk about luck!). I refueled, (10.47gal.) ICE started on 1 bar. recharged some and went to dealer to have check engine light cleared. Dealer said all they did was clear the check engine light. Only code was I ran out of gas!

130 Miles later... back at dealer. MPG at 39 and going down! ICE runs all the time. Can't do stealth for more than 100 feet. Battery gauge bounces like a rubber ball, 8 bars to 2 bars. Dealer says the computer does NOT show any problem. They don't know why the battery indicator is jumping around but EVERYTHING IS OK! I have another appointment this Saturday with another eXpert! SOC =64 %, Delta state of charge 87%.

In a different post I read someone made a comment like the system will have to "learn" for a while before the MPG goes back up? If this is true how long will it take? I have put on ~150miles and it is still very bad.

I am beginning to think this may also be a safety issue. My regen breaking kicks out as high as 29Mph. If you are use to it at 8mph it makes for a quick adjustment in peddle pressure. I am also afraid that if I had to step on it and the battery happened to be at a low point, I will not get any boost from the battery?

 

Just had my 35,000 mile service done. When I bought my Prius my mileage averaged 48 to 51 mpg (with recommended tire pressure). Over this past 2 3/4 years of easy driving the mileage has slowly incremented down to what is now an average of ~39 mpg. Some of the more significant increments occurred after Toyota dealer service but none were due to to overfilled oil, tire pressure changes, or the like.

I'll be taking my car in for one more warranty service visit soon and will mention this as something I want fixed. Other issues include:

. Misaligned steering wheel since steering shaft replacement (recall)

. Gas tank issue (fills to 7.5 gal when gauge says empty, have to slowly add after that, sometimes gasoline gushes out on removing nozzle)

. Main display getting dimmer with time (no longer viable on a bright day)

Otherwise, the car has been pretty good with no real repair issues.

 

This doesn't apply directly to the possible dealer problem, but I have 40k on my '04 and have always got 48-50 mpg. Even with round trip arizona mountain driving to 8000 feet. My wife has 10k on her new '06 and under exactly the same conditions averages around 44mpg.

Dealer says insignificant, I say unacceptable and will meet with the district guy soon.

Same tire pressure, temp, driver( at times), route, fuel, speed, ad nausium.

The only thing haven't checked is oil viscosity, can't believe this matters that much???

I don't think you can find a better comparison test then this, any new thoughts??