Going to try to post important details to help figure out the problem. I'm the 2nd owner of a 2000 ranger 2 wheel drive with the 4 cylinder motor that has 8 spark plugs. I got it about 5 years ago at 87k miles. After few months driving the check engine light comes on and code is something about EGR valve. Dad and I replaced the EGR valve but the light comes back even though the motor seems to be fine. I know its wrong but I've been driving it to this day with the light on up to 140k. In that time I change the oil at least 4 times a year, replaced rotors, replaced pads, replaced alternator, and replaced battery. But the original owner put new belts, hoses, tires and other ware/tare items on it only a few months before it was put up for sale by his son since the dad couldn't drive anymore.
The only issue in that time was maybe 1-2 times a year I would go to start it and it would run rough but after barely touching the gas it would clear out and stop after a couple minutes of driving. No big deal since it would only happen once or twice a year if that but check engine light is on which I know is wrong.
Well in the past couple months its been doing the rough idle after startup more and more. This past week it would do it every time I would head home from work. If I let go of the gas pedal after I start it will die. Just have to barely push it to keep it running. After I drive it a couple minutes it will run without me having to touch the pedal but it runs rougher that it used to like its barely above the point where it will die. So I started looking online about EGR system issues and came across this trouble shooting guide:
Part 1 -How to Test the Ford EGR Valve and DPFE Sensor.
I need to borrow a vacuum tool with pressure gauge with gauge and use it to test the EGR first but I tested the DPFE sensor. With the key on I get the 5v from the plug but when its plugged into the sensor I only get .2volts. Follow the guide and with it started it still shows .2 volts. I put tubing over the top of the EGR valve and with my girl friend barely pressing the pedal to get a normal idle . I breathe in the the tube slightly to create the vacuum and the motor starts to stall and the voltage at the sensor doesn't go up. So I figure the DPFE sensor is bad because the guide and videos shows the voltage goes up if you create a vacuum on top of the EGR valve. Buy a new one at autozone and it still the same.
I guess I need to get the exact code that is tripping the check engine light and I need to borrow a vacuum tool with pressure gauge to test the EGR valve first. Also should see if voltage goes up with the new DPFE sensor. Haven't looked at the idle adjustment because it would feel like I'm fixing the symptom and not the problem unless its common for the idle to loosen up allowing it drop over time.
I want it to run right and get the check engine light resolved. Any help or guidance is much appreciated.