Okay so first things first I'm not really all of a car guy but I would like to get into working on my own vehicle. So as the title says I have a 1999 Ford Explorer SOHC 4x4 with about 160,000 miles. The issue I am having is the the check engine light came on and its running a P0171 and P0174 code running to lean which my guess is a MAFS problem or a vacuum leak. The problems that are happening are

1) It doesnt accelerate fast at all as in if I push the gas pedal all the way down the RPMS will rise very slowly with my MPH not moving at all.

2) It seems when Im drive it for to long as it gets hotter or up a large hill and I come to a stop it will want to stall and die.Also if I turn it off and then back on the idle is very ruff and will not move even some times there are some popping sounds coming from the exhaust.

Now I have replaced the MAFS with a used one for its cheaper but the problems are still there. I had one of my Granddads retired Ford friends look at it and he couldnt find a leak anywhere even though it does sound like there is. Then when I told him about the popping we looked in the back of the exhaust and saw that there was a lot of what seemed to be steel wool coming out. I ended up getting all that I could out which seems to be all of it, I dont know if someone is messing with me by putting stuff in it or if people actually wrap their muffler/exhaust with steel wool. My plan is to take off the Catalytic Converters off (yes there's two) and just going ahead and hollowing them out and getting someone I know to cut the exhaust and see if theres anymore of the steel wool. But I really need help knowing if my exhaust problem is causing the too lean to pop up or if there may be another problem. If you have any questions I will post ASAP.

P.S. - When I was running codes and before I cleared them a code came up for a Heated O2 sensor I dont know if that could also cause a problem.

P.P.S. Thanks for the help before hand.

 

Welcome to FTE.

You may have an intake o-ring leak, very common in these engines.

You may be better off finding a shop to run this all down for you. These are not fun motors to work on, and yours sounds like it needs several things run down.

If the cats are dead, it's because it was running poorly and dumping fuel into them. Removing them may clear the exhaust system, but it will not fix the poor running.