Black smoke, bogging, 5 MPG Highway!

[nlauren]

I bought a 91 Explorer Sport a month or so ago. When I first brought it home from the dealer it was fine, the gas mileage was decent, around 17 or so highway, sometimes even 18 or 19. Last week a ton of black smoke started coming out of it, its all over the snow where I let it warm up in the morning, its really thick. Plus, my gas mileage has gone down to about 5 or 6 miles to the gallon, which, as a 19 year old college kid, I cant even close to handle. Also, I've noticed that if I go about 40 or so miles or more, the engine will rev up a little, then let back down, going in a cycle.

Anything anyone can do to help me would be greatly appreciated...I cant afford this anymore!

Thanks

 

[Mike 92 XLT]

Sounds like your fuel pressure regulator went. Do a search for it and you should be able to find tons of info. Check the fuel pressure at the Schrader Valve on the right (passenger) side fuel rail. It should be around 35-40 PSI (I think). If it's significantly higher, your regulator is bad. It's not too expensive or difficult to replace.

BTW, welcome to the site!

peace

Mike