1999 Ford E150, V6
Symptoms: Truck runs great, however on random startups the truck runs very rough. A restart will fix it. Once it was running great for 30 minutes, then loss of power on hill, barely made it up.
Weird symptom: Started up truck, running rough, 5 minutes later the temperature gauge is bouncing and rising with the roughness of the engine. Tacks out to the red, still bouncing with the rough running engine then the temperature warning light comes on. Pull over, turn off engine, wait 60 seconds, turn it back on and everything runs fine for the remainder of that trip.

P1409 error code, something's wrong with the EGR Vacuum Regulator (EVR).

1. Replaced spark plugs; OEM.
2. Spark plug cables were at 13 ohms, replaced with new.

3. EVR reads 36 ohms through the solenoid. This is within the tolerance. GOOD

4. EVR red to Power-train Control Module (PCM) pin 47: 700 ohms! BAD
4.a However the EVR red does get 11.7 volts with Key On Engine Off.
5. EVR ground to block: <5 ohms. GOOD

6. I cut the plug off the EVR wire that plugs into the EVR to see if the connection was bad there. Direct from red wire at EVR end to PCM is still 700 ohms.

Questions:
Q1. Is there anything between the EVR and PCM? Could the connection be bad at a junction, fuse or anything? Does anyone have a wiring diagram for this?
Q2. Is the Weird Symptom at the top of this post about the temperature gauge relevant? I didn't want it to throw me off of a regular check list of possible problems.

Thank you for any help you can give! I appreciate it.

 

i have a 2000 e-150 same symtem, it had a major vacuum leak under throttle body.