1999 ford taurus miss when going up hill

These are the symptoms of a bad coil or spark plug. Have them checked.

check for the spark plug leads.inspect in the night under the hood if u start the engine and see the spark from leads.if u find spark leads good then check the distributor cap whether it is wet or moist inside?

Hello first of all

No that will not really help what controls missing is bad fuel air mixture depending on what o2 sensor you change this may or may not affect this only the o2 sensor before the cat converter will affect this as it runs mixture.

That being said here is what i would check being a mechanic for 5 years with ford and 3 with bmw first check spark in all cylinders make sure it is blue not orange do this by pulling out plugs leave them connected to wire and have someone start the care and check the color of spark.

If blue in all your good if orange in any replace the coils and or coil if you have more that one.

Then replace the camshaft position sensor and if possible the crankshaft position sensor the crank controls starting spark and the cam running spark but they work together.

If this all fails and you have had a recent tune up plugs wires coils air filter fuel filter ect

If all this fails you need to see a shop as unless you have alt of tools and time its beyond most folks reach.

I hope this helps if so please 4 thumbs up thanks

You notice the miss when going up a hill because you are putting the motor under load, sounds like time for tune-up, pretty sure the miss is there all time, but you just notice it more when under load

Start with the simple things first. When was the last time you had a complete tune up? "Missing" could indicate bad spark plugs, bad spark plug wires, or bad cylinders. Change the plugs first, then go from there.

Fuel injector??

How many miles? Have you ever serviced the spark plugs? I will assume it's a 5.4 V8, since it's more common than a 4.6.

In my experience with 5.4's, at about 120-140k miles, the coil-on-plugs tend to start dying. You will only feel the miss on acceleration and under heavy load, but may feel a slight wobble when the truck is at idle.
Not knowing how experienced you are with vehicles, I will give a slight overview. The traditional older vehicle has a single coil that delivers high-voltage to all of the spark plugs to cause the spark and ignite the fuel in the cylinders.
On these newer vehicles, each spark plug has it's own coil that is attached to the spark plug.
Unfortunately, there is no easy way to determine which coil is not firing without unplugging the wiring harness on each coil and seeing if the behavior of the engine changes.
However, in my experience, once one coil dies, the others aren't far behind. It may be worth your while to change them all at once.
The downside is, they are not cheap at about $43/ea at autozone. The upside, is they are extremely easy to change yourself. Simply unplug the electrical connector off of each coil at the spark plug. Then remove the 8mm bolt that holds down the coil. Pull off the sparkplug and replace.

I changed a full set in the parking lot of a hotel in South Fl last year, and it took me about 1 hour.

depends but it possible you have a bad injector. Could be bad plug,wire or coil.You have to a few things to eliminate.

The a/c makes it worse because you are asking the engine to pull a load missing one cylinder. If you have alternate transport or like working on a hot engine you can take number 3 wire to the autoparts and get one wire to match length. You may want 1 plug in case wire doesn't help.

Well this could be in your timing. As cars get some miles on them the timing chain stretches therefore causing you car to lose alot of power.So you may want to have your timing set on this car. Also I had a taurus that had a bad torque converter, and it lost alot of power on hills and under loads, also when i gunned the gas pedal. so try the timing first. Hopefully you dont have a bad head gasket or a cracked head these symptoms you are describing are all signs of head gaskets or blown heads