Bad Gas Mileage Solutions

[Frisckey1]

OK, I have read all I can stand on some of the suggestions for solving poor gas mileage.

I recently have experienced some VERY poor gas mileage and was wondering if you all could tell me a couple of things:

1) MAF Sensor...how to check and is it easy/cheap to replace or would it be easier to have mechanic do it and just pay?

2) Where are the 02 sensors and how to check?

3) FPR...same thing...where and worth doing yourself to save bucks?...also does any one know approximate costs of these parts if needing replaced?

Thanks!

 

[65Matt]

1. ?
2. O2 sensors are attached to the exhaust pipes after the headers. Basically, if its been over 60k since they were replaced, get some new ones. They are a little tricky to install. The threads can seize up, and sometimes it requires a special wrench.
3. ?

Replace your PCV valve. It's around $2.

 

[Wucko]

MAF it is in the air intake next to your air filter. Very easy to check and clean. You will need some security torx head to get it off...about $15 to$20 for a set.

FPR - cost $75 I changed mine in about 1 1/2 hours and it solved my problem. I had been getting a chekc engine light for about 6 months. Finally, the diagphram in the FPR gave out and the engine would not run. It was sucking fuel direcly into the cylinders and fouling the plugs.

 

[rock883]

1-Like they said it is easy to check, mine doesn't have the torx bits, I guess the previous owner switched them to a phillips head screw. I think you would only need to clean it off. I am not sure what exactly to use, but you can chekc on the main page under the tips section and it should be there.

2-Your 95 probably has 2 O2 sensors, an upstream and a downstream. If you want, you can get a special socket which has a cutaway part in it to allow the wires that come out of the sensor to go out the side of the socket. You could just get a regualr wrench that will fit on it and unplug the sensor first, then take it off, but this way is much harder. They are hard to detach, and may require some thinking to get them unplugged. I had to get ontop of my engine and reach down and unplug it. Then when you put the new one in twist the wires counterclockwise a bit, then screw it into the hole in the exhaust, then tighten it. What I did was go buy the special socket, take really good care to not scratch it, or anyhting, use it, then return it saying I found my old one and didn't need the new one. Usually the package they come in is easy to open without destroying it. The O2 sensors cost around $30 each.

3-The FPR can be a bit trickey to get to, at least for my 91 it was. I had to drain the coolant a little to take the upper rad. hose off to get to the bolts easier. It is located on the fuel rail, which is right where the upper and lower intake manifolds meet. You should chekc a Haynes or Chilton manual to see what it loks like. There are 2 different ones for the early models, and I had to take mine off first to tell Advance Auto which one i had so I got the right part. But, when changing the FPR, be sure to releive the fuel system's pressure. This can be done by pulling the carpet back on the pass. side floorbaord, there should be a wire harness that has a connector, undo this, and try starting up the car, it probably won't, then that is good. Or you can do it by getting a guage w/ a bleeder valve on it and that will do the trick too, but it will cost you more to get that tool. But the FPR costs about $80

3-

 

[Frisckey1]

Hey Thanks!

This is the info I was looking for.

I am more interested in the MAF Sensor, cuz so far from what I have read, most of the other indicators come along with the check engine light. My light hasn't come on...so I am guessing I probably just need to do a bit of cleaning...hopefully no replacing!

Thanks so much for the responses!!!

 

[kubben]

What is FPR?

 

[Triton46]

FPR=Fuel Pressure Regulator.

Got mine with 33% off from carparts for about $40. If you have a 91 or 92 there are two different ones, make sure you get the right part number.

 

[kubben]

I'm pulling about 250 a tank on my 1996 XLT. Is that normal? The only modification I have is K&N Air Filter. What should I look into to boost it rather than the chip.

 

[Bill Kemp]

You might also make sure your thermostat is OK and your temp. guage is in the middle of the "normal" range.
This effected my mileage.

 

[amigo]

Thanks for the info Bill. My thermostat barely moves after the truck has been running for an hour or more. I know my Cat is bad and needs replaced, but wasn't sure what else would effect gas milage. I was getting about 250-300 on a tank now i'm lucky to get 200.

 

[Cevigney]

I'll have to try these myself. Getting about 3 mpg >.<