Alright I had an earlier post in the forums about my 1997 2.3L 4cyl Ranger that had a rough idle. I went ahead and took out the MAF to inspect it and it looked o.k it wasn't dirty and appeared to be in good condition and I replaced the IAC valve hoping that would fix the problem. After doing all of that I went to start her up and for the first 2-3 minutes the motor sounded great. The rough idling was gone and I thought I had the problem solved. Then the motor started rough idling again this time worse than before. It was so bad that it was hardly running at all and it finally died. Now every time I start it it runs good for about 2-3 minutes then it will start sputtering and running horrible for a few minutes then right when you think it's going to die the idle picks up and it will run fine for a couple of minutes and it just keeps repeating this process until it eventually dies. There is an extreme loss of power while driving in 4th and 5th gears and if you put it in neutral and rev the motor up and let off of the gas then it will sputter out and die. Has anyone else came across these symptoms? Any idea what could be causing this? It used to run rough but ever since I removed the MAF to inspect it it has gotten so bad I can't even drive it. Help please!!!

are you getting any codes? does your CEL come on when you first trun the key? try unhooking the wire to the MAF and running it? maybe cleaning the maf is just a coincidence and the real problem is just getting worse. Have you changed the fuel filter? any idea what your fuel pressure is? did you check the vacuum lien to the FPR for gas.? did you check vacuum lines? pull out the pcv and check it?

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

I did find a loose vacuum line I'm going to fix it and see what happens. I replaced the fuel filter last week. I was going to check all vacuum lines but I don't have the proper tools to do it. I'll fix the loose vacuum line that I did find and I'll check the PCV valve and report back. Thanks modelageek.

I just read your other thread........if you are getting a p0301 that is your issue not the MAF. were you getting the misfire before you changed the plugs and wires? what plugs and wires did you use?.

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

Ya I was getting the misfire and thats when I decided to change all the plugs and wires but that didn't seem to help the problem at all. All the plug wires were OEM and the plugs were Bosch.

try to be clearer about what you are saying. are you getting a misfire code now? even a pending code?..........if you were getting a p0301 before the plugs and wire switch and you are still getting the code now then here is my suggestion

1)put a large bottle of techron in the fuel tank to clean up the injector.
2)suspect the coil packs and or the ICM= ignition control module. auto parts stores can test these for you. have them test them a few times. you can test the resistance of the coil packs with a multimeter.

the recommended plugs and wires for these engines are Autolite or Motorcraft, Bosch plugs suck.

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

I was suspecting the coil packs as the culprit I need to check them.

I agree with modelageek ,, Autolite or Motorcraft or nothing. And they are a whole lot cheeper than Bosch too.

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2000 Ranger XLT 2WD 2.5 auto. 2nd owner.