| monami54 |
| Hi! I am brand new to this forum. I am hoping someone out there has a suggetion to help me. I have a 2005 Murano with only 40,00 miles on it. When I first bought it 9 months ago, I was getting 23 mniles to the gallon on the highway and 18 - 20 in the city. But it steadily went down from there to the 14.5 miles per gallon range city and highway, I took it in for a tune-up and the mechanic said it didn't need new sparks bgecause they were platinum and were good for 100,000 miles. Well, now I am only getting 13.9 miles to the gallon. Any ideas how to get better gas mileage? I have tried using a higher grade gas but that hasn't changed anything. Thanks for any help. |
|
|
| njjoe |
monami54-
Welcome to the forum.
Your mechanic is correct, there is nothing to "tune-up" on your MO. The spark plugs are designed to go 105,000 miles (169,000km).
Has your highway MPG dropped? Has your driving style changed much (i.e. more short drives, less highway driving)?
The decrease in MPG could be attributed to a number of factors:
- dirty air filter
- partially clogged catalytic converter
- bad air/fuel ratio sensor(s)
- ECM out of spec (controls ignition timing & air/fuel ratio)
Has your "Check Engine" come on recently?
-njjoe |
|
|
| dalsox |
| Bear in mind that with the cold weather comes significantly worse gas mileage. In Wisconsin I'm averaging 14.5 mpg overall this time of year. I get 20-21 in the summer. |
|
|
| shelland |
| Wow - I'll consider myself lucky. I've had my MO since May, and have averaged about 21 in that timeframe. The lowest I've seen all winter The lowest I've seen all winter is 18 once or twice. |
|
|
| biggun |
| My gas mileage drops about 2-4 mpg during the winter. Warming up the car is probably one of the main cuprits. Who knows, maybe the AWD is operating more from poor road conditions (causing poor gas mileage), but I will never know since there is no indicator to tell you when it is functioning. |
|
|
| monami54 |
Thanks everyone for your helpful replies! When it got the best mileage was in July and of course we've had some very cold -30 to -40 days this winter. All said, though, it started to be poor in October and now it is around 40 degress F. Here's waht the mechanic did:
the report said: 1. Tune-up - didn't need one
2. check injection and flush, clean throttle body
$135.00
That's basically what was done. Should I go back? Even when it was warmer out it was not nearly as good as when we first bought it and drove it home . |
|
|
| Eric L. |
The same is happening to me as well, and I'm attributing it to the cold weather. It takes much longer for the engine to warm up and get off the warm up cycle (open loop mode) when it is cold out - you get the best fuel economy when the engine is operating in closed loop mode after it is fully warmed up. A lot of short trips kills gas mileage.
I too have thought about various maintenance to improve fuel economy, and have done everything myself short of changing the spark plugs or doing a full injector cleaning (I did run a couple bottles of Techron Concentrate though). No change to fuel economy, so I can only blame on the cold weather. |
|
|
| shelland |
quote:
No change to fuel economy, so I can only blame on the cold weather.
My MO must like -20 temps. :D |
|
|
|
