Spark Plugs Fouling Out

[89danger_ranger]

I have an 89 Ranger and I just recently installed autolite and they then fouled out so i replaced them with motorcraft plugs and now i can tell they are starting to foul out. What should i do get higher temp plugs?

Also any ideas what to check for getting better gas milage I am only getting around 12mpg and have no power could It be the Fuel Pressure Regualtor?

 

[HIPCHIP]

I'm no mechanic by any stretch of the imagination, so hopefully someone else will chime in.

Are you blowing any smoke? If it's white smoke, then I believe you're burning oil, and you could have leaking valve guides, which will foul the plugs (I had this happen to me a long time a go).

If you're blowing black smoke, I believe that's from too much gas, so you could investigate that.

Also, check your oil to see if it's kind of a milky white, and check your radiator to see if it is milky. If so, you may have a blown head gasket, which can also foul the plugs.

I know I'm not much help, just trying to give you a direction to look at.

 

[BlackBII]

When you say fouling out, what do you mean? What do the plugs look like?

 

[Ranger44]

Yes, there is a reason you are fouling out plugs. Maybe a rich condition? Are the plugs black and sooty?

 

[IMenriched]

have you pulled codes??

When was the last tune up?? other than plugs

if you're having a rich run situation, try changing the thermo sensor for the engine computer...they are not to expensive, if that hasn't been changed yet. If they are operating in a incorrect range then they send a erronious signal to the engine computer, (it thinks then is running too cold), So it goes into a cold over fueling state/ heavy choke.

changing the thermostat with a good 180* will help too....it could be weak not allowing it to get warm enough for the other sensors to read correctly.

yes the FPR could also be a culprit....test fuel pressure, should be around 30-40PSI.
a quick way to check the FPR is to pull the little vacuum line off the back side of the FPR (engine off), and if fuel dribbles out...it's pretty much toast. But if no fuel is present in the little line doesn't mean it is necessarly good either, pressure test will help determine that.

check that and if those thing don't correct it then there is other things that could be getting the lousy MPG's