What would cause a 2000 Ford Explorer XLT 4.0 V6 to miss and be slow on hills?

Tom its actually cuts off turning sharply left or right Since I posted my question My engine whistles when I rev it What could be causing that? Would a clogged catalytic converter also cause the whistling sound?

On my misfire issue Tom I replaced the coil pack again because the old one was still under warranty the engine light hasn't came back on In park the engine will rev up good Is there any other diagnosis you could give me also on the miss? Could be wrong though could the loss of power on hills and takeoff also come from the miss Back in the early 2000's I had a 1986 S10 Blazer 4x4 with a 2.8 V6 with 200,000 miles at the time the catalytic convertor was totally stopped up but it ran on all cylinders but yes very,very slow on hills at times drop from 65 down to 25 at the top in passing gear Don't know if it was mentioned before but it has an exhaust leak somewhere from the manifold on the passenger side to the first converterWould the exhaust leak also cause a bad miss?

Tom, Now my Explorer is showing trouble codes Engine too lean Banks 1 & 2 I do feel the catalytic converter has alot to do with it but is there any new things it could be too because it has a new fuel pump/strainer/sending unit and new plugs wires and a new coil pack Would an exhaust leak cause it to run too lean?

Johnny so what was the outcome of this? I am having the same thing happen on my 2003 explorer just hit 144,000 the 1st thing to happen was the abs. Or overdrive orange light blinks the one u use for slowing down going down hills after that about two weeks later my car stalled making a sharp left. Three weeks later now I am having troubles when driving it's all really sluggish almost like it's slipping and you have to play with the gas pedal to keep it moving I was starting to think it was maybe the transmission but sounds like you had the same thing happen so what was the outcome also the cost to fix it. Thanks

Mine ended up being the fuel pump/sending unit giving out but the fuel mixture ran lean for so long both catalytic convertors became stopped up thus having to replace them Maybe the way your problem sounds you may need a new fuel filter and fuel system cleaner If your engine light is on go to your nearest parts store and they should have a hand held computer that should tell whats going on free of charge The only other thing I can tell you is take it to a Ford dealership where they have a diagnostic machine to hook it to but they have very expensive labor rates I bought my own OBD2 handheld that tells trouble codes but they cost over $200.00 for a good one I sometimes just unhook both battery terminals for a few minutes to reset the computer but 9 times out of 10 the light turns back on Hope this helps Frida!

So the slipping and sluggish take off had nothing to do with the transmission? Did you do the work yourself or take it to a shop. I have a guy that is pretty fair price but this sounds like it still could be expensive I am dropping it off on Monday still going to try and drive it in.

It's my o/d. Light that blinks I found another format where they where saying it was the transmission when the o, d light flashes and is taking off sluggish. But your sounded just like mine I had that car stall when I did the sharp left had to stop and restart it. I was thinking it was electrical. I still think whatever it is will cost some money

Cutting off, when turning hard one way or the other, is usually a bad power steering pressure switch on the power steering pressure hose. Changing this out will cure the stalling on turn problems. You have done the logical thing with your tune up, with one major exception. You didn't do a compression test. It is quite possible you have a cylinder down, causing the misfire. The only true way to do a tune up, on a high mileage vehicle, is to perform a compression test. You will find any misfires that are engine related, to wear or carbon or etc. If it a low cylinder, there is a chance of carbon build up on the valves. You can sometimes clear that problem with a good upper valve lubricant/cleaner, or sometime with water. Being it's fuel injected, the water idea is pretty much moot, but the cleaners can help. Also, the 4.0 throttle body can get gummed up inside, and can use a good behind the butterfly cleaning. There are two small air holes inside the butterfly that supply air to the engine for idle. They get black from the dirty air and fill in the holes. A good can of Berryman's B12 will cure that. I'm a retired Ford partsman/line mechanic. These are common items to check on the 4.0 engine. The S197 Mustang with the 4.0 has the same problems, but are easily cured with a good cleaning, if it isn't an internal engine problem. Hope this help you some.

I have a 2000 Ford Explorer. Just went to 250 000 mikes it started missing so I had a guy change plugs and wires he brought it back with number 1 still missing it started cutting off going down road .I have taken it to numerous places their tester reads misfires on 3 plugs .the last place read mass air flow sensor .I took it to K&S pros and tires and they tried coil pack didn't fix it .it is at Pro Tech now .waiting to hear from them .I don't have money to out a lot if work into it .What do you think the issue is ?

I am having similar issues, did you find out what the problem was?

I have a 2000 Ford Explorer it sounds like something has dropped and it runs and moves it’s just hard to turn