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Strange gas mileage issue


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I hope I am sensing sarcasm there... Always hard to tell thru the interweb..

 

Anyways, I think something along these lines might be going on with my Tribeca.. I have been driving mostly on the interstate, and I am only getting roughly 18 MPG. I should be getting at least 20, if not 22. But the dealer says there is nothing wrong.

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I hope I am sensing sarcasm there... Always hard to tell thru the interweb..

 

Anyways, I think something along these lines might be going on with my Tribeca.. I have been driving mostly on the interstate, and I am only getting roughly 18 MPG. I should be getting at least 20, if not 22. But the dealer says there is nothing wrong.

 

 

Ok no more speaking of that heathen vehical.

 

2 mpg can just be seasonal. Blu drops that much in winter and summer (cold vs AC use) and can actually hit 30 on the highway spring and fall.

 

In the winter he can go as low as 16 from his usual 21ish.

 

nipper

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Heathen? Its factory original, except for some computer mods in the EEPROM. But anyways..

 

I would normally agree, but last year, driving the same trip, at the same speed, and it was MUCH colder, I got 21.2. This year, 18.9.

 

Something I am going to have to keep an eye on..

 

 

factory original... except for some computer mods:rolleyes:

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pff. I replaced my o2 sensor $100 later. Fuel economy seemed to have gotten worse. Was usually around 400-450km before the low fuel light would come on. Now I am around 300km range when the light comes on. So let me tell you what I have done and replaced. fuel filter, air filter,pcv, plugs, wires, before all this dumped some injector cleaner (could indeed be the issue and made the issue worse this is not a very good injector cleaner) , o2 sensor, um cleaned the throttle body, iac valve. Not sure what else. I think I have a vacuum leak. going to put some clamps on hoses like for the IAC, and pcv. Also going to try some good name brand injector cleaner like STP. Maybe I should run a tank of premium through the car too.

 

Car seems to drive pretty smooth. I do have a bit of a heavy foot SOMETIMES, but cruising along I keep a steady pace and coast as much as possible. Tires are a bit wider then stock and stickier very soft with a high side wall. Been looking for a nice 96-99 LGT sedan. Nothing around here locally. Till then going to keep tinkering with this car. I will try a few things (injector cleaner and premium) and get back to you guys on if it made a big difference. Maybe wheels to if I can find some decent ones for under $200.

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One of the front brakes could be a issue as the slider is not perfect. All the others have good sliders, and I did not find a dragging parking brake issue. There is a possibility of a bad wheel bearing though. The car DOES have 323,000km now. Exhaust converters have been replaced so hopefully there not clogged by now. What I have noticed is the exhaust is pretty loud sometimes. If a injector is indeed stuck, will it trip a engine light?

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One of the front brakes could be a issue as the slider is not perfect. All the others have good sliders, and I did not find a dragging parking brake issue. There is a possibility of a bad wheel bearing though. The car DOES have 323,000km now. Exhaust converters have been replaced so hopefully there not clogged by now. What I have noticed is the exhaust is pretty loud sometimes. If a injector is indeed stuck, will it trip a engine light?

 

323,000 km (200,700 miles), the car is entitled to drop a few mpg. At that mileage it may be time for a compression test to check the overall health of the engine.

 

nipper

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Ya I am going to check. It is kind of funny the way the car drives. Seems faster when I do only 1/2 throttle. Seems slower at full throttle. Especially if I am launching like if I just jump on it quick to get the power light to come on, and only go around 1/2 throttle its pretty quick. If I floor it, it seems slow, really odd. even on the highway to make a pass it seems to catch speed better at 1/2 throttle compared to full throttle. :-\

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I don't really notice anything when I look at the rear view mirror. I also tried another used MAF sensor(sensor looked clean), made no difference. At the beginning seemed faster, could have just been in my head though.

 

What I do notice is sometimes I find my idle to drop very low, doesn't shut off though. If I stare at the rpm guage I can see it flucuating a bit sometimes. Other days it holds it steady and it is a bit higher idle. Going to grap a few hose claps the style that the radiator hoses use preferably. Use them on the PCV valve hose, and IAC valve hose. The pcv valve sees pretty loose IMO, the IAC hose I can pull off pretty easy to.

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filled up today. 204miles on 8.9gal just about 23mpg :-\ its not horrible for commuting to work but not as good as it was. maybe my engine has given up. 230,000 miles and most of that i have no idea how well the previous owner maintained it. It does use a quart or so of oil between oil changes.

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filled up today. 204miles on 8.9gal just about 23mpg :-\ its not horrible for commuting to work but not as good as it was. maybe my engine has given up. 230,000 miles and most of that i have no idea how well the previous owner maintained it. It does use a quart or so of oil between oil changes.

 

 

Well it is winter, 23 is not bad. Check your tire inflation, change your filters and PCV valve, and maybe get a sompresion test.

 

The PCV valve fouling usually causes oil burning.

 

 

nipper

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With the mileage on Your engine, I'd say that 3-4 MPG drop in the winter is prolly about right.

 

It's a combination of many variables that is eating up Your fuel economy.

 

Prolly the biggest culprit is the very poor performing fuel that We are forced to burn in the USA. Not only does the Ethanol content go up in the winter mo's, but they add other performance robbing chemmies also.

 

Can You elaborate on the "exhaust seeming loud at times"?

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