Fuel Economy Suddenly Down By 15%-20%?!?
 

Hello all:

I have 2003 AWD XLS Outlander with 68,000 miles. I used to get about 21.5-22 mpg in combined city/highway. I was pretty happy with that. However, in mid-December, within a few days, my fuel economy went to about 18.5 mpg (sometimes even in the 17.5 mpg range)! WTF?!? That is more in the V6 range of fuel economy. I've noticed a slight grinding sound when I am coasting less than 15 mph and my Outlander seems to slow down more than my other awd vehicle.

Anyway, I've brougt it to a couple of dealers and a brake place to have it checked out. The brake place did not find anything wrong (and I had the front pads replaced because they were getting pretty thin). Then I took it to a dealer to have them test drive it and to listen to the grinding sound. Well, wouldn't you know it, the mechanic must have been deaf - he could not hear anything abnormal. Then I took it to another dealer to have it thoroughly checked out - the driveshaft, wheel bearings, oxygen sensors, computer diagnostic test, etc. Same thing - nothing seemed wrong. The only thing they found was a somewhat dirty air filter - that was replaced, but the poor fuel economy is still there.

In my personal opinion, it is one of the wheel bearings that is worn (especially because of the grinding sound and the rolling resistance - the problem is that the mechanics' way to check wheel bearings is to simply rock the wheel fromn side-to-side to see if there is any play (mine seems tight, according to them). Is this really a good way to check it? I'm assuming that a worn wheel bearing can exhibit some other symptoms than this.

Any ideas? With my annual driving distances, this reduced fuel economy will cost me about $300 - $400 more per year. I love the way my Outlander handles and drives (especially after putting some performance tires). It could use more power, but I'm fine with it. I try to drive very conservatively and rarely go over 3,000 rpm. My low fuel light now comes on around 220 miles on a full tank of gas - previously it was in the 280 - 290 miles. Also, I don't think it is the winter because last winter, I was still getting about 21-22 mpg.

Thanks in advance for any advice!

- TinkerMan

RE: Fuel Economy Suddenly Down By 15%-20%?!?
 

i say pull the plugs, and put some new ones. I did mine like at 30k so more than likely you are over due for a swap. I know the dealer puts ngk's but they use the low series of the brand. i think i put in some bosch double platinum and did see a minimal increase in performance and mileage, but my plugs werent bad so you will most likely see a greater improvement.

RE: Fuel Economy Suddenly Down By 15%-20%?!?
 

Thank the good Lord somebody else realizes this too! Hahahahahahaaa...the Outlander sucks gas like a V6 for sure! I've tried everything to help with this but nothing...[:@]

RE: Fuel Economy Suddenly Down By 15%-20%?!?
 

yes it does but he said that it just recently went down so something must be wrong. but on the good side i recently went on a 100 mile trip and got 25 mpg on the highway with about 30 miles before that in the city. as it stands i can get almost 20 all city and if i remember correctly i can get 28mpg all city.

RE: Fuel Economy Suddenly Down By 15%-20%?!?
 

Yeah, I could get around 26.5 mpg on the highway (90%+ highway driving). The thing is rated at 20-26 mpg (but we all know how accurate that is, right?) and my combined city/highway of about 22 was in the ballpark - so I was happy.

Also, could it be the winter blend fuels? That is what the dealer says it may be. But, a 15-20% drop in fuel economy??? Come on! It that were the case, many more folks would be complaining to the gas companies about their gas.

Anyway, I'll try swapping out the plugs. The last dealer checked to see if the other dealer swapped out the plugs at my 60,000 mile service (it has about 69,000 miles now), and it seemed like they did - they probably put in cheapy ones, though.