Okay. Tom, maybe this is another thing up your alley. So far the information you've provided has been a big help so maybe I can ask for a little more advice.

For those who do not know my truck:

• Truck: Ranger
• Year: 1990
• Engine: 2.3 Lima
• Trans: 5 Speed Manual
• Miles: 83,445

Recently Replaced:

• Oil Pressure Switch
• Oil Pan Gasket
• Crank Position Sensor
• Spark Plugs
• Plug Wireset
• Ignition Control Module
• Driver Side Coilpack

After I got done with all of this crap on my Ranger, I noticed that it was driving great! But...today I was on my way to school and BAM! My engine idle started hitting (presumably because I do not have a tachometer) about 3000RPM and lowering down to about 2500RPM and from there, every time I am not in gear it decided to fluctuate between 2500RPM and 3000RPM. Crazy style too.

Now, I got to school, and getting closer to it at a stop light the truck basically died. It was almost at 100'ish RPM. I gave it gas, and BAM. I hear a continuous hissing noise from under my hood. Haven't diagnosed it fully yet because I just got home and its 12AM.

Now, every time I stop at a light or in traffic or whatever it may be, I have to give it gas every other second, like a small push on the pedal, to make sure the truck doesn't die. Also, every time I am out of gear and my RPM's are at an 'idle' state, I get continuous hissing from somewhere, I get no power loss or anything, just really weird idle RPM's and hissing when my foot is not on the gas basically. It is strange. I think It is some sort of Vacuum leak but I am not sure.

To get a better picture of the 'hissing' noise, it is the same hissing as you would hear when letting the air out of a tire. That is the best way I could describe it.

 

You might have blown one of the vacuum lines off its fitting. Once off, it would pull air into the intake, make the idle weak and fluttery. Depending on the system, you have a MAF or MAP sensor that fiddles with the amount of fuel being injected based on air flow or manifold vacuum. Unmetered air can lead to high idle, weak idle, fluctuating idle, etc. A MAF may also cause hesitation on acceleration, while the MAP will show more erratic idle.
Look under the hood in daylight for something out of place.
tom

 

im guessing vacuum leak as well take some carb cleaner and spray your vacuum lines youll find it really easy

 

Thank you again Tom. It was the MAF. It wiggled loose from the intake manifold. I bolted it back on and now the problem ceases to exist.

Thanks again Tom, you're the best. =D