Jeep seems to burn through a tank-full of gas too quick

[Down4U]

To give you a quick background, I recently took my truck to the shop to get a few items repaired. It needed a new fuel pump (long story, but to make it short I let the tank go all the way to empty before re-filling), and while at it the mechanic replaced the fuel filter for me. Right around the same time my truck also needed one of the tranny seals changed (I got the tranny oil changed a couple of months ago and while it sat garaged in my house almost all the tranny oil spilled out). The engine seals also needed to get replaced (don't exactly know what these are, all I know is that they seal off the engine valves for the coolant).

A few weeks ago I got into the habit of pouring a bottle of fuel injector cleaner in my gas tank every time I filled her up. The engine has been idling a bit more rough than I can remember. My pop thought that it was probably dirty injectors, so I started getting the fuel injector cleaner bottles.

The rough idling has gotten a little better, but what's now odd is that the truck seems to burn through a tank full of gas much quicker than it ever did before.

I'm not sure if this has to do with the new fuel pump delivering more PSI on the fuel line, consequently having the engine burn more gas than it needs to, or if there's something bizarre going on with the fuel injection system, or whatever else that ya'll can think of.

For those car enthusiasts out there, what do you think?

 

[CraigRT]

my car seems to be awful on gas in the winter.. not good... kinda blows. seems to get better in the summer.

 

[Down4U]

I got this truck around March, so it was still fairly cold outside. That's a good point though, I guess I'll pay more attention this summer.

 

[CraigRT]

Originally posted by: Down4U
I got this truck around March, so it was still fairly cold outside. That's a good point though, I guess I'll pay more attention this summer.

apparently the winter does make a huge difference... so yeah for sure keep that in mind

 

[iamwiz82]

what engine, what model jeep? In top shape, the 4.0L should get around 20mpg. The 2.5L is pretty close to that figure too. Where is your engine leaking? The rear main seal is pretty common in it. Is it leaking near the back, by the transmission? What temp. is the engine running at, also? 210 degrees is optimum for fuel consumption versus power

 

[Down4U]

Originally posted by: iamwiz82
what engine, what model jeep? In top shape, the 4.0L should get around 20mpg. The 2.5L is pretty close to that figure too. Where is your engine leaking? The rear main seal is pretty common in it. Is it leaking near the back, by the transmission? What temp. is the engine running at, also? 210 degrees is optimum for fuel consumption versus power

'96 Grand Cherokee Laredo, 4.0L 6-cylinder. The engine was leaking cooland toward the front, right over the front differential. He changed the so called engine seals. Ever since he did that I haven't had to refill the cooland reservoir at all, and the leaking is gone. It always runs at 210 degress once it warms up.

 

[konichiwa]

Could be because it gets less miles to the gallon than a bulldozer?

 

[iamwiz82]

my grand cherokee gets less than 10mpg, for reference

 

[Down4U]

Ugh! Oh my God are you serious?!? LOL When I first got the truck I remember only having to fill up about twice a week with $32. Now I seem to have to refill every three days with $40.

 

[iamwiz82]

how many miles per gallon are you getting right now?

 

[Down4U]

I haven't kept track, but it sure is less than what it was a year ago.

 

[Down4U]

Anyone wanna guess?

 

[T2T III]

Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BG-44K. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

 

[Eli]

Originally posted by: wje
Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BK-44G. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

Is it better than Techron?

 

[Quixfire]

Originally posted by: iamwiz82
my grand cherokee gets less than 10mpg, for reference

That's because you have those big monstar tires mounted on it.

 

[Quixfire]

Originally posted by: Eli

Originally posted by: wje
Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BK-44G. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

Is it better than Techron?

Yes it is, I have used it before as well.

 

[Eli]

Originally posted by: Quixfire

Originally posted by: Eli

Originally posted by: wje
Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BK-44G. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

Is it better than Techron?

Yes it is, I have used it before as well.

I'll have to look into it. As far as I knew, Techron was the best you could get.. although I suppose that isn't counting things that you can't get at any autoparts store, though.

What makes it so special? Just super heavy duty?

Anyway, as far as the problem.. Get just a general tune up. It can help a lot.

 

[stev0]

it's probably just the winter weather. i noticed that my 00' F150 v8 gets 2-3 miles to the gallon less than when i do in the summer.

 

[Siddhartha]

Trucks and suvs get bad gas mileage.

 

[Down4U]

Originally posted by: wje
Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BK-44G. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

Ahh.. I guess I won't be buying any more STP bottles from Strauss.. I knew it had something to do with the gas they sell at different times of the year. I mean, I truly remember only having to refill once every two weeks, and that's because I really don't drive my truck much since I don't take it to work. Now every time I take any given 40-mile round trip within the city for about three times it guzzles almost half tank.

Someone said that it might be the vaccum valves leaking air? Or some sensor making it burn too much fuel. Who knows.

 

[iamwiz82]

Originally posted by: Quixfire

Originally posted by: iamwiz82
my grand cherokee gets less than 10mpg, for reference

That's because you have those big monstar tires mounted on it.

34's this summer!

Down4U, Unless you are getting under 15-16, you do not have a problem other than winter.

 

[Down4U]

Originally posted by: Quixfire

Originally posted by: iamwiz82
my grand cherokee gets less than 10mpg, for reference

That's because you have those big monstar tires mounted on it.

So much for getting me those 20 inch chromes with the low profile tires.

 

[Quixfire]

Originally posted by: Down4U
Anyone wanna guess?

First off you need to understand that colder weather and special blended fuel can affect your fuel mileage up to 20%. Plus the price of gas has jumped quite a bit in the last month, example: last month it cost $12-13 to fill up my car, 92Escort GT, today it cost $21. You need to track your mileage better in order to understand the differences.

Here is a simple method.

Next fill-up reset you trip meter.
The following fill-up record the number of gallons used and miles driven.
Then divide the number of miles by the number of gallons and there is your MPG.

300/10 = 30 MPG

OK?

 

[Quixfire]

Originally posted by: iamwiz82

Originally posted by: Quixfire

Originally posted by: iamwiz82
my grand cherokee gets less than 10mpg, for reference

That's because you have those big monstar tires mounted on it.

34's this summer!

Down4U, Unless you are getting under 15-16, you do not have a problem other than winter.

You still looking for a new/used rear axle?

 

[T2T III]

Originally posted by: Eli

Originally posted by: Quixfire

Originally posted by: Eli

Originally posted by: wje
Not only does the cold weather affect your gas mileage, but so does the blend of gas that gets distributed during the winter months. The blend of gasoline alone could rob you of a few M.P.G. Also, in regards to the injector cleaner that you've been using, you might want to save your money. The STP stuff that you buy at the local auto parts store is a waste of time. Get BG Products BK-44G injector cleaner. It runs about $21 - $22 a can. Most parts counters of car dealerships sell the stuff. It's also distributed to some local service stations. However, it's not available at local auto parts stores. I've used all of the other stuff before, but it was waste of money compared to the BG-44K. This is also the stuff that Pat Goss advertises on his weekly radio show: Goss' Garage.

Is it better than Techron?

Yes it is, I have used it before as well.

I'll have to look into it. As far as I knew, Techron was the best you could get.. although I suppose that isn't counting things that you can't get at any autoparts store, though.

What makes it so special? Just super heavy duty?

Anyway, as far as the problem.. Get just a general tune up. It can help a lot.

Yes, it is quite heavy / thick. You run one can (10 or 12 oz.) through a full tank of gas. It's done a tremendous job of keeping my injectors clean. Search DejaNews for "BG Products Injector" - and you'll see a lot of responses on the use of their injector cleaner.