went from 17mph to 12.2 mpg help

[drick]

Hi,

I dont know what is wrong. I've went from 17mpg to 12.2mph now. I can't even get 300mpg a tank. I dont know what could be the problem does anyone have any clues? Please help! email me please at drick@baraboo.com
any help is appreciated!

 

[gtmazz]

I had the same problem.here's a start
Two things to check right away!

Fuel presure regulator and injectors.
The fuel presure reg going bad is a common problem.When is goes bad it dumps extra fuel into the cylinders.Also a leaky injector that wont hold presure will leak gas into the cylinder when the engine is not running.

I had this problem were the gas leaked into the cylinder and then into the oil pan!!
I ran my motor for about 1 month before i relized that there was gas in my oil!
not a good mixture!! well, i also noticed a small rod nock!! Can u say new motor!

Check your fuel presure and also check your oil to see if there is any sign of gas in it.

It happened to me and dont want to see happen to a fellow Explorer!

 

[kvo]

Here is what happened to me and it turned out to be the fuel pressure regulator.

Symptoms:
1) Mileage cut almost in half (16-17) to (8-9).
2) No power going uphill, even at a slight incline. Not much acceleration either.
3) Blackened tail pipe.

There could be other reasons why your mileage is cut in half, try a search on the low mileage subject, there were a lot of postings on this subject. Also, look into investing in a Code Scanner.

Good Luck,
kvo.

[This message has been edited by kvo (edited 08-18-1999).]

 

[kvo]

DRICK -

It all depends on the kind of gear ratio and tires you have on your Explorer. If you have the high ratio (3.05, 3.23, or 3.55) and street tires, definitely, you'll get more mileage out of a tank but for me with a lift kit, winch, steel bumper, roof racks, larger tires, lower gear (4.10), and other accesories, I'm real happy to get 300-310 out of a full tank (18-19 gallons) for highway. In the city, I usually get about 280-290 per tank.

 

[Jordan714]

I am having a similiar problem.

24,000 Miles on the Explorer
20 gallon Tank
250 miles per Tank

12.5 MPG That sucks!

The only thing I have done to my 1998 XLT that would affect performance is 31x10.5x15 Tires and Custom Exhaust System. What do you all think about that? It shouldn't be that bad should it?

Any help would be grand! - Jordan

 

[drick]

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[This message has been edited by drick (edited 08-18-1999).]

 

[drick]

I found out today I had a bad fan it was cracked and im getting one put in tomorrow most likely. Could that of been my problem? If I still get bad gas mileage I'm gonna check the fuel regulator and so on...also how much would a new regulator cost if that is the problem?

 

[drick]

Thanks for the help, I'll go try the injectors and filter. After reading more on here I find out that some people think 15mpg is good for their explorer. I know that I got between 380-400 miles on a tank a gas before this problem. It seems some explorers do a lot better then others...


92' XLT 4X4 Explorer

 

[Skip Pendle]

The fuel pressure regulator responds to intake manifold vacuum: the higher the vacuum the lower the fuel rail pressure.

Make this quick check: identify the vacuum line going to the fuel regulator and see if it has any gasoline in it. A common failure mode is the failure of the regulator diaphram. If you detect gasoline in the line, you need a new regulator.

 

[JR 91 Sport]

If the fuel pressure is ok try checking the oxygen sensor. These will sometimes go bad and cause the engine to run rich = decreased gas mileage. This is a cheaper and easier (ie. do it yourself) fix to try than tearing out the fuel rail if nothing shows up with the pressure test. Doubt it was your fan unless the clutch was locked up. If this was the case then yes your mileage would decrease. Good luck!

I get around 21-22mpg highway out of my '91 sport, 5spd, 3.55 gears. But it also has 103K and BFG AT's which hurts the mileage somewhat.

I've got no cents, JR

 

[OzMaToz]

I was getting some seriously sucky gas mileage for awhile and couldnt figure it out either. It could be a number of things. For me it all started when my a/c compressor went bad, and eventually the main bearing in the pulley started to go. This caused a large strain on the engine. Once I replaced it, I was getting 18mpg again. Good luck in finding the problem!

------------------
The Oz Man -94XLT-
ozmatoz@hotmail.com

 

[S.Matsushige]

I think Oz-Man has a good point Drick. Try removing the fan belt and checking all the pulleys for wear. My mileage dropped a little when my tensioner and idler pulley bearings went bad. Any accessive drag on your engine could cause your mileage to drop or something that is making your engine work harder than it has to.