Here is what I have found on DTC 628 for you;
E4OD Transmission Control Indicator Lamp (TCIL) Flashing Diagnostic Trouble Codes 62, 628 and/or 1728 & transmission shifts hard for 90-96 TSB 98-4-19
Source: by Ford via miesk5 (Al M) at comcast.net
http://home.comcast.net/~miesk5/technical_...e_bulletins.htm
DTC 628; "...code 628 can be caused by a mechanical problem or electrical problem. First thing to do is to check power to the solenoid connector at the transmission. These solenoids are 12 volt solenoids, not 5 volts......I have attached a few pictures for reference. Unplug the transmission connector and check the VPWR wire for 12 volts first with the key on at the harness itself. Then if OK, check the solenoid resistance with an OHM meter on the 200 OHM scale through the pin on the connector coming out of the transmission marked TCC & VPWR pins. Should be 0.98 to 1.6 OHMS as MTB has said. I usually used a special transmission tester tool, but this is the only way you can do it. I have seen many of these code 628 in the past, and I'm sorry to say 95% have been internal Mechanical failure. These tests for the solenoids are only going to tell you if the solenoid is open or within spec. It will not tell you if a piece of junk is stuck in the solenoid causing it to bleed pressure to the TCC, therefore giving you a rough running engine, shuddering feeling or stall in 2nd, 3rd, or 4th gear caused by the Torque converter clutch being applied at the wrong time..."
Source: by Fordace at lincolnsonline.com
http://www.lincolnsonline.com/forum/showthread.php?p=498844
Solenoid Pack Connector Location; "...It's on the passenger side of the transmission. You'll need to remove a small heat shield (two bolts) next to the catalytic converter, and probably clean away a TON of gunk before yanking it. Ford wasn't too bright in designing the placement of this connector. The connector has a single press-in tab latching it in place, IIRC..."
Source: by SigEpBlue
Solenoid Pack Connector Location; ..."I just pulled an e4od out of a 92 and that connector is VERY easy to get to if you are willing to pull your carpet. There is a very convenient access panel in the center there and it makes reaching the top and sides of the tranny very easy..."
Source: by gunterelectric226
& this is what our friend Steve wrote elsewhere;
"The entire procedure is too long to post, but here's just one step:
Transmission Solenoids and Sensors Resistance Tests
EPC Solenoid
> Set ohmmeter to 100-200 ohm range.
> Connect negative lead of ohmmeter to the electronic pressure control (EPC) jack.
> Connect positive lead of ohmmeter to the vehicle power (VPWR) jack.
> Record resistance.
> Refer to the following charts for values.
If out of specification, refer to