1993 explorer fuel milage issue

[gooddrwho]

I bought my explorer and did a full tune-up. At first all was fine until i put a little over 600 miles on it. Then the explorer started to cut out the power as i tried to accelerate (when i hit the gas the rpms would drop to 1k). Not sure what to do I messed with it and realized that somewhere in my exhaust system i had a clog. To fix this i unscrewed the driver side O2 sensor and tucked it underneath the car since i was unable to get it unplugged. I noticed a difference and the explorer responded a lot better but because of the sensor i was only getting 12 mpg which was less then the original 17 mpg. after several days driving with it out i went muddying and all was good. Until later that night when i went to slow down for a turn on a back road it just died on me. Later on it would die off and on if i stopped giving it gas while going down the highway. This got fixed when i put the O2 sensor back in. The performance was back, but, now i only get 8 miles to the gallon and i am blowing out black smoke and just have the 2 caties hooked up and not the muffler since that is where the clog is at. What do I do? How do i reset the computer memory? What are my options and what might cause me to burn way to much fuel?

 

[Anime]

What kind of spark plugs did you use? Using cheap plugs can cause issues, generally OE Motorcraft platinum plugs are best.

The issue sounds like it may have just been a bad oxygen sensor, so you might get your mileage back to normal if you replace them both.

You can throw on an aftermarket muffler, I'd suggest one that's made for the 93-94 Explorer since the hanger is on the muffler, but you can use a "universal" muffler with an offset in/center out if you come up with some way to stick a hanger on there.

http://www.explorerforum.com/forums/showthread.php?t=182514


You can reset the computer by disconnecting the positive battery cable for awhile, then reconnecting it. Be sure to let the engine idle for 5 minutes or so, then take it for a spin so the computer can "re-learn" some basic functions. It will take a few days for it to learn everything again, but you should be able to tell if the problem is fixed pretty quickly.

 

[the_don]

pull your plugs and recheck the gap, and see what color they are burning. you can reset the ecm by pulling the battery cable for an hour, but you should pull codes before you reset.after the reset it take 20 run cycles(i believe) for the ecm to "relearn" the sensors.

 

[Anime]

Yeah, be sure to check the gap and see what condition the plugs are in. If they are fouled up with oil, there may be cracks in the head and/or a blown head gasket, and the oxygen sensor on that side went because it got slathered with oil.

If that's the case, you can expect the catalytic converters will probably have oil in them as well, coating the elements inside, causing them to run hot and not work, giving you the black/blue exhaust.

You can throw on a single 3-way catalytic conveter rather than shelling out the $200+ for a new dual-converter replacement.

 

[Jason94sport]

Replace the 02's.

 

[smegun]

if you drive hiway miles you may see the benifit of good milage means everthing is working in your timing in fuel and exhoust systems

startups around town and short drives i dont see anything 15 16 17 18 ..... there is somewhat of a miracle for milage on a long patient consistant pedal trip its more than the figures even give for the truck maybe even exponential at 65 70 mph .....thats the miracle of injection and knock i dont see much of the benifit unless in overdrive with a good tickover ....to me there is too much wasted time on short trips around town that could use more driving pleasure where milage is not impressive or power for that matter unless your doing a little slipery dirt driven let me know if you guys come up with key on power

 

[OneofMany]

if you drive hiway miles you may see the benifit of good milage means everthing is working in your timing in fuel and exhoust systems

startups around town and short drives i dont see anything 15 16 17 18 ..... there is somewhat of a miracle for milage on a long patient consistant pedal trip its more than the figures even give for the truck maybe even exponential at 65 70 mph .....thats the miracle of injection and knock i dont see much of the benifit unless in overdrive with a good tickover ....to me there is too much wasted time on short trips around town that could use more driving pleasure where milage is not impressive or power for that matter unless your doing a little slipery dirt driven let me know if you guys come up with key on power

I have no idea what all that salad means.