I've got a 2000 Exp XLT w/ just over 137K on it 4x4. I had power loss like a slight hiccup but not a buck while going up steep grades, and a lack of response passed 50mph or so. I'd assumed it was the whole in the muffler, threw on a new Super 44 and the power loss is a lot less but I still notice it. I have no Codes bein thrown at all. I threw 2 bottles of Dry Gas on 1/4 of a tank of gas, drove it till E and got another 1/2 tank n change, a week later a can n 1/2 of Seafoam in the tank on an 1/8th of a tank of gas. Drained the tank to E and threw in enough $ for 1/2 a tank of gas. Response picked up better around town and on the highway, but it didn't last. Going up hill on a steep grade, I'll notice the truck will just drift from 50mph down to 45 while keeping steady throttle, if I try to give it more gas the truck either barely responds, or if it does, I can smell eggs from the Cats but only briefly. I put an entire bottle of Seafoam thru the booster line let it sit for 45min, started it up and let it idle white smoke for 10 minutes, then drove the truck about 2 miles before it stopped smoking. Got a little better response and take off from stops with it. But still have the issue going up hill.

I spoke to a former Ford Employee who said if it were the cats I should smell them all the time not only up hill. And a Ford Mechanic I spoke to said maybe Cats but possibly EGR.

Now I also have a tick coming from the front passenger side of the truck, I'm not sure if it's a valve tap or an injector or something else. I had topped off the oil w/ Castrol Syn 5w-20 about a month ago as I've done since I bought the truck in 03'. And recently put about 1/2 a bottle of Lucas Synthetic Stabilizer in. Still ticks.

Any help would be greatly appreciated.

 

Sounds like a COP that hasn't thrown a code yet. Find the spot that keeps it missing during the power loss and it will eventually throw a code.

 

The hiccup itself is way too quick, and happens at varying RPM's. But the gradual power loss is constant up hill once I hit 50, I gradually drop to 45, right after the hiccup. The hiccup only lasts about a second maybe two.

 

Try the uphill test with a full tank of fuel. If the problem is gone with the full tank of fuel then you need a new fuel pump.

 

Thanks I'll give that a try Alloro, I always value your input. Over the summer the fuel pump I assume was making a mid pitch humming sound extremely loud, but only did it for 1 day, and it never occurred again, but that was deff coming from the fuel tank area. Albeit recently I've been hearing a high pitch version of the same sound but from the front of the truck, I think only cause the 2 times it's done it was when it was below 30 degrees and very windy upwards of 40mph gusts here recently in NJ. And only right after I start the truck. But that was about a week ago. It may have been near the fuel tank, if it happens again, I'll hunt it down.

On a side note, last night when I went up the same hill it does it all the time, it did NOT do it last night, and I did notice I was tacked at 3100RPM's and the truck didn't shift till I leveled out. I rarely hit that high an RPM for long. I usually hit the hill at 50, but this time I hit the hill at about 40 cause I had a PA driver in front of me that didn't know what the right pedal was for, or what a speed limit was. So I stepped on it to finally pass them, and that's when I noticed I was at 50 with those RPM's and I had only dropped to 49mph from 51 and that was keeping the pedal at the same position. RPM's stayed the same. I had just over a 1/4 tank.

Oh forgot to mention in the 1st post my truck has the 4.6L Vin 6.

 

Sorry I haven't updated recently, but I've had a lot going on trying to get set for school and such. But I wanted to update.

I no longer have the hiccup since I replaced the Fuel Filter, but I still have power loss. And now my gas gauge is dancing from time to time, which only started on Sat or Sun this passed wknd. It will either show more gas than I have by a 1/4 tank, or light up the Low Fuel light after putting in $30 worth. At a stop it will level out, and then creep down, and stutter back up. It didn't do it at all 2day. I'm planning on replacing the entire fuel assembly and pump in the next week or so. I still have not thrown a code in quite a while.

 

Did you ever figure out your problem going uphill? I have a 03' Expedition 5.4L that is doing the same thing.

 

I'd start thinking about COPs. Does it go away if you click off the over drive?

 

yeah when I turned O/D off it does the same thing. I was driving up Vail Pass in CO and I had a hard time going 40 MPH.

 

Doesn't sound like coils then, if it was coils and it was that bad it would have set a code.

 

I am going to change the fuel filter, but I also heard it might be the catalytic converter or a block in the exhaust, such as flattened somewhere.

 

I'm still suffering the same issue but I cleaned out the throttle body spacer EGR channels, thinking that was it, some guys had the same issue in the Mustang Forums, and that fixed it, but with the Expy same engine, not the same fix, and put that back together about 2 months ago. Last week I pulled the downstream o2 sensors, been driving without since, granted with the Super 44 on the exhaust my Expy sounds mean, but I have less power up hill, and then it's also heating up the heat shielding on the under carriage. Oddly though, after a rain early yesterday morning, I tackled the hill as I do everyday and I didn't lose any power, which is a 1st in a long time, and 1st in 10 days since I pulled the o2 sensors. I was about to put them back in this passed weekend, but one of them had white flakes pouring out of it, so I shook it a bit, and realized something was not right, grabbed a screw driver n spread the inlets a bit, appears the ceramic around the prob shattered, so ordering new o2 sensors soon from Advanvced, now that I found a 20% off code. I'll do the downstreams this weekend, and maybe tackle the upstreams next, but the UP's I never took out. I picked up a new TPS as well, but haven't put it in yet, gonna wait till I do the o2 sensors and drive to n from work for a week, see how my uphill power is.

It almost feels like when it hiccups it's coming from the rear, sounds mad, but that's how it feels 1/2 way up any hill. I have to hit a hill at 2600ish RPM's in order to break 45mph. If I don't I crawl up the hill at 40 and slowly work my way up to 50, eventually.

I spoke to a guy with a 2000 5.4 as opposed to my 4.6, randomly grabbing coffee one morning and he has the same issue. He already had the trans rebuilt at about 80K and is Expy has 140K on it, same as mine, but my trans hasn't given me issue, so I think I can factor out the trans as the issue. Oddly a steeper grade hill, which is very short at that, gives me the same issue, but 1/2 way up, the truck seems to get life out of it, which is what makes me think it's the TPS. I hit that hill at 25-30mph since it's in a school zone, and my power comes all of a sudden 1/2 way up. The longer hill I hit everyday near my house, makes the truck crawl, it's longer and only slightly less steep.

 

I think it's the spark plugs. I was having the same problem with my 05 even on flat surface when I accelerate too hard.

I replaced plugs last weekend and the problem is gone and it drives like new now.

 

I was going to change the spark plugs, but I had a couple people tell me they didn't think that was it. How difficult was it to replace them? Is it worth doing it myself?

 

If you are still using the original ones, the chance they cause your problem is very high...

Your 2000 model is much easier than 05 because you won't have the "plug separation problem". But still if you've never done it before, plan a whole day for it.

You will also need some special tools made: a 7mm socket with flexible extension is a must to reach those ridiculously tight #4 and #8 locations. I have to super glue the socket to the extension before I lose it.

Good luck!