My 93 f250 has a fault code 624, is in limp mode and will not accept over 10% throtle without missing horribly. I just installed a B&M shift kit and a reman solenoid body. I was carefull about the kit and dont think anything got out of place but like I stated above I keep getting the 624 code. I have checked my wiring and have continuity through the white/yellow wire from the PCM to the trans plug and the epc solenoid is checking 4.9 ohms resitance which is within spec. I didnt have the problem before the install which is leading me to belive the epc check ball and spring may not be sitting correctly. Any input is appreciated. Thanks JD

 

I'm having the exact same problem with my 93 bronco w/ 5.8. I also get the 624 eec code. Did you end up figuring out what solved the problem?

 

This code indicates an electrical problem. You have a wiring issue.

 

Awesome, thanks so much

 

if the epc ball is stuck in the bore when the pcm tells the epc solenoid to push up on the ball and the ball does not move it will cause the rest of the ecm surge correct? I am having the same issues as the rest but without any codes . and factory transmission. new solenoid block . new mlps trans and mlps harness have been checked with an ohm meter .001 on all wires then all the way to eec4 connector with same result . swapped ecm same thing . soon an I unplug either one of the epc solenoid wires truck runs perfect . no continuity to engine ground with test harness installed either side of epc solenoid. all 4 solenoids are within spec via test harness and astg transmission manual. ever seen a stuck epc ball in an e4od?

 

What do you mean by " the rest of the ecm surge correct".
The ecm or EEC/PCM module doe not surge as far as I know.

 

there is a big draw on epc solenoid . red wire and white wire with ye stripe. the red wire is ecm relay witch feeds epc injectors iac tab and tad solenoid and egr regulator . the epc solenoid has such a draw that it is killing the rest of the sensors and the truck is running bad . once the epc is unplugged truck runs perfect. I just put a reman solenoid block in the trans and its doing same thing . swapped ecms same thing . swaped trans harness same thing . tested reman solenoid block completely ( ATSG and ford factory manual tested perfect . hooked epc red wire to battery charger + and white with yellow stripe to a switch and then to battery charger ground . flip the switch for a super short time you can hear solenoid clicking (like its moving like it should) could epc ball be stuck in valve body bore causing the solenoid to have a big amp draw even thow I hear it clicking it might not me able to push the ball up like it should? causing the solenoid to draw to much and killing everything else on the circuit?

 

94 ford van 351w e4od ecm pin 38 epc sig return (ground) circuit 925 ecm pin 57 ecm relay feed to sensors and epc + circuit 361

 

I have 4.5 ohms on solenoid (within specs)

 

can I drive it with the epc unplugged ? or will it ruin the transmission . trans works fine. 125k on the truck no mods all stock. and yes I checked the engine body grounds. I am not new to the ford eec4 or 5 . or the rwd transmissions . I have just never seen a stuck epc ball . and the fluid I drained was totally clean and was almost nothing on pan magnet ( everything like brand new inside) . truck is all original I bought from 1st owner at 99k

 

Note the red wire from the PCM Power relay goes a lot of other places too. It feeds all the fuel injectors + what all you noted above.
The red wire is feed by a fuse link at the starter relay and it is controlled by the PCM Power relay.

I do not see how any solenoid in the solenoid pack could pull down the voltage on the red wire. You do not state any voltage readings with the transmission solenoid pack plug plugged in or with the plug removed from the transmission.

 

well there is a massive arc from the sig return side of the solenoid when when I isolate it from the harness and manualy connect it either to epc return or to installed battery ground . with that kind of arc it almost has to create a voltage drop through the rest of the circuit . it arks like touching a direct - to a direct + from the battery . I do understand there is going to be a load on the circuit because of the nature of a solenoid . but this one is big and I have done the same test to the other 3 solenoids in the block and you hardly see an ark at all . what would be nice is to see the factory load specs (amp draw ) because I do not have that info here . I am not pulling the block out till I can confirm its out of spec. I am now kind ruling out stuck epc ball because I notice the trans goes into drive and reverse much harder when solenoid is unplugged . and once plugged back in it is normal . next is actual voltage drop test on circuit 361 while connected and engine running and load test on sig return to ground . I have seen about 10 posts through the board with various dates with the same issue and no report on the cure . I guess leave it to the roofer to figure it out . one person sold his truck because after 3 months of posting and a few trips to various shops . and about 10 different tech`s looking at it no one found the issue . there is also a diesel guy on a different fourm having the same type of issue currently he has been chasing it for over a month with a 4r100. i think the load test is going to tell the story .

 

If you are shorting the return wire to ground and you are getting a big arc the solenoids coils are shorted. The PCM computer grounds this wire to control the solenoid (oil pressure).



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Cut from my Ford manual:

PINPOINT TEST E: DIAGNOSTIC TROUBLE CODE: 99/624, 625, EPC CIRCUIT FAILURES


E4 CHECK SOLENOID FOR SHORT TO GROUND

Check for continuity between B- (engine ground) and appropriate jack with an ohmmeter or other low current tester (less than 200 milliamps).


Connection should show infinite resistance (no continuity).

Is there continuity?

Yes
REPLACE solenoid body assembly. RECORD and ERASE codes. Repeat On-Board Diagnostics.

 

like I stated above . the complete solenoid block tests good by ATSG manual (done all tests 3 times to make sure and has nothing on load testing ) with trans harness totally unplugged checking power I have 14.2 volts on the fluke 87v soon as its plugged in the voltage fluctuates down to 11-7.5 volts . amp draw is 4-7 amps. now that I have established the remanufactured transtar block that I installed lastnight is defective (my original did the same thing just not as bad ). here is the million dollar question. what do you think my chances are that the separator plate gaskets will take a second swap and not leak between the passages? I did use a torque wrench for install .