As for the intermittent stalling and other issues, I would suggest opening your ECM cases and checking for capacitor leakage, it's a very common issue and before you drive yourself crazy it's a simple enough thing to check off the list. And if they are leaking, then you've found at least one issue.
I have a 1995 Ford E-150 5.8L with an E4OD transmission. I had an issue where the engine would buck and stumble and would periodically spark knock when driving 40 to 50 MPH around 1400 to 1800 RPM part throttle. I spent 3 weeks troubleshooting the issue. The engine had to be at operating temperature and running in “closed loop”.
This condition never set any DTC’s, which I checked for frequently with a scan tool. The engine acted like it was quickly being shut off and back on, it did not act like a cylinder or coil was misfiring. I also ran the KOEO and KOER tests with the scan tool and everything worked correctly. Being that the distributor cap & rotor, spark plugs and fuel filter were due for a replacement I installed new parts but none of those parts eliminated or even improved the bucking and stumbling.
Although I have had a factory service manual since the van was new, I did not have the diagnostic manual which I needed to have to check all the other engine components. Luckily I found a 1995 factory diagnostic manual on eBay for $30.
Using the Ford diagnostic manual I checked the operation of the MAP, TPS, ECT Sensor, IAT Sensor, EGR Valve, EGR Position Sensor, EGR Vacuum Solenoid, O2 Sensor and they were all functioning correctly. I also checked the timing, fuel pressure, and I did a coil load test and plug wire load test and they were all OK. I also drove the vehicle in “open loop” mode numerous times to see if the condition occurred which it did not. I was able to put the engine into “open loop” various ways: removed SPOUT; disconnected ECT sensor; disconnected O2 sensor.
Since the other components checked out as good I next focused on the Engine Control Module. I removed the ECM and removed the cover to look for any anomalies. I found a very small area of corrosion on the circuit board that was only visible with a magnifying glass. Being that all the other components were working correctly I then suspected the ECM as the cause of the issue.
I ordered a Remanufactured Cardone ECM at AdvanceAutoParts.com for $72 after using coupon code TRT30 and received it in two days. Right before I swapped out the ECM I drove the van just to make sure the engine still bucked and stumbled which it did. Once the new ECM was installed I drove the van and the issue was gone. I have driven the van about 150 miles with the new ECM and it is still driving good.