Update,

For anyone who still may come across this or still following this thread:

I checked my plugs to my transmission and greased them up, they all seemed fine to me. Keep in mind I replaced the plug and shift solenoid aprox. two weeks ago so they are new with no corrosion or water contamination, (I checked anyways).

Fluid is at it's appropriate level, and it shifts softer, but still bumps and makes a loud noise when you engage it into drive/ reverse.

After driving for over 10 minutes, engaging into reverse usually bogs down the engine and it will stall without applying pressure to excelerator. Sitting at a stop sign in drive causes the engine to bog down and rise and bog and rise, and all sorts of rattling with the exhaust do to the low idle. Not sure what that's about still.

Also something new, when you start the engine it will have a medium idle typical of when you start your car in the morning and it warms up for a few seconds. Well my truck will have a medium high idle and then drop instantly with in seconds of starting. No rattling or bogging though. Just interesting.

Also... The transition from first gear to second seems too early. It will usually shift before I cross the yellow line when pulling out of a parking lot, at like 10mph.

Any advice is greatly appreciated. I'm so sick of working on this, at this point the smell of trans fluid makes me nauseous.

 

your description sounds like a failing tps with a modern computer controlled engine.they can rise and lower the throttle.sometimes even hold WOT on you.my previous '96 f150/300 did that.luckily she was pointed uphill lol.
also your incorrectly timed e40d shift symptoms match that of a failing tps as well.

 

Hmmm, that would be really frustrating because I just ordered and replaced the TPS last week. I think that's the day I started this thread actually. I'll look into proper installation videos to see if may i needed to adjust the throttle or something before I installed it. If anyone has any links to that off the top of their head lol that'd be great.

I just read a thread about the IAC valve suggesting that causes poor idle problems and reverse issuse, any thoughts on that?

I wish my truck was a '96, I feel ford went really cheap with my year! haha

 

well it could be a bad vacuum line and unrelated as well.it's just something to keep in mind.
your priority of course is dealing with code 624
Solenoid/circuit failure -Electronic Pressure Control (EPC) current is high

so don't let me sidetrack ya.if your unsure,you can have a trans shop test your solenoid pack to rule out a failing epcs
by chance you don't know or have installed an inline shift kit/pressure riser of any sort? no known resistor mods that your aware of or anything?

 

Arg that bloody code just won't go away will it... I've had this code since day one. Before and after I replaced my solenoids, each time.

No there is no shift mod on the tranny. I mean, as far as I can tell. When I replaced my solenoid the first and second time it looked exactly what I saw online, and there is no external modifications. So to my knowledge it all looked stock to me.

I had to replace my starter solenoid today, maybe there really just is a mess with my wiring/ circuitry somewhere!

Hey, btw thanks for not giving up on me yet!

 

How are you measuring the ATF level? there is a proper procedure, you can't just measure it with the truck off. It sounds like you have a low fluid level, which would allow the filter to hang (even fall) in the pan, which in turn would cause the bogging down when you come to a stop or you try to back up (even killing the engine). A low fluid level would also explain the high ATF temperature triggering codes.

 

I usually check it after I get home, or if not and it's cold I'll take it for a drive so it warms up and then let it drain into the pan for a few minutes before I check it. So the fluid is warm/ at operating temp.

I've read about that on this website, how it's necessary to check it when it's warm because the fluid expands/ contracts with heat. When it's warm is when the level should read in the hash marks on the dipstick.

Is that right?

 

Yes, it has to be read at operating temperature while iddling in park. I'm kind of sad it wasn't just a dumb mistake by you, it would be an easy fix.

 

You and me both!

 

Well, no one has offered this suggestion as of yet.

GROUNDS, GROUNDS, GROUNDS !!!!!!!!!!!!!!!

The 4.9's are extremely dependent on the ground at the starter.
If the negative battery cable has corrosion, either visable or hidden under the jacket, your "block ground" will be resistive.

If the ground at the starter isn't near perfect, the transmission/block ground will seek out another less resistive ground.

I'll bet if you feel the fender next to the battery when the truck warms up, it'll be rather warm or hot to the touch (lots of resistance).

If so, the block ground (which should be going directly to the negative post on the battery) is running through the frame to the radiator support, to the passenger fender, through the 10 guage wire from the fender to the battery.

You need to clean (wire brush in a drill) the surface of the starter @ that ground, the negative battery cable @ the block ground, the frame @ the negative cable clamp crimp, the cable crimp where it bolts to the frame, and the interior of the negative clamp @ the battery, AND the negative post on the battery.
It wouldn't hurt to clean up the ground on the fender next to the battery either.

I resolved most of my hard shifts (especially in reverse) by cleaning up the above grounds.

I'm shifting pretty smooth now.

There is also the possibility that your PCM is "starting to fail".
Others have reported that replacing their PCM has resolved their shifting problems too.

Give the grounds some attention first and see what happens.

Bob

 

Update:

Well I'm real close to taking my 12 gauge to this thing.

Today I took off and cleaned my IAC valve after reading a post about it affecting idle and reverse issues, and really scrubbed it out with carb cleaner and a few small brushes. There was a lot of caked on gunk. It looked new after i was finished.

I noticed my transmission is overheating now, which is a new problem,its been cool all winter each time I checked it. How do I know it's over heating? It's smokey after a 30 minute drive, it almost burnt my hand when I touched the pan, and is puking fluid.

My fluid reads just near the hash marks cold, and near perfect warm. I blew the lines with a compressor wondering if it had gotten clogged and thats what was causing the over heating but there was no residue and the lines where clear of obstructions.

I took your advice bob, and went through some of the grounds and actually bought a new ground cable when I bought the carb cleaner today, they seem ok but I polished up some of the connections with a wire brush and sand paper. I reaplced the one on the engine block to the body because it was the only one corroded.

Also, this is new and interesting: When I floor it ( I was pretty frustrated after all my efforts today), in about third gear I start to coast and my idle drops to, well idle no bogging or reving, and this is with my pedal to the floor. WTF does that mean?

I know some of you think I should just take it in but we're talking a 1500-2200 fix and honestly I'd rather just invest that into a new one. Its only valued at $2000 kb and has rusty fenders. I was really hoping to make it through the summer with this thing and get a nicer vehicle this fall. Anyone with advice thanks in advance.

 

Drop the pan and see if there is something there, you can check how to in this write-up I just finished: https://www.ford-trucks.com/forums/1...l#post13059337 just jump to the shift kit install.

 

At this point, before you drive it anymore, I'd remove the PCM and look for leaking capacitors or something burnt on the circuit board.

Here's a little reading you need to do and what to look for.
Click here:A9x ECM's (and same years ECM's) Failures Due to Age

As I stated earlier, "There is also the possibility that your PCM is "starting to fail". Others have reported that replacing their PCM has resolved their shifting problems too".

After all, the PCM DOES CONTROL the transmission.

Bob

 

My Ford Service manual defines Code 624 as this: indicates a failure of EPC circuit.

There is no indication if that means a short or open circuit.

Possible Causes:

Open or short in harnesses (internal/external).

Solenoid damaged electrically.


In light of you already replacing the solenoid pack twice I suspect you have a wiring problem. I HIGHLY suggest you check the wiring from the PCM to the solenoid pack.

The EPC solenoid is controlled by Pin 38 on the PCM connector. The corresponding pin on the transmission solenoid connector is Pin 11.

The solenoid pack connector:


Pin 12 provides power to the EPC and the rest of the solenoids. I suspect the issue is the way the PCM controls the ground to the EPC solenoid.

 

I notice my filter doesn't have a clip to hold it in place! That's a big deal right?! I think I'll make one right now from scrape and drop my pan before bed and fix that. Damn. My filter probably doesn't get a very good seal... So thanks for that lead Encho. I remember thinking that when I replaced the filter how it just hangs there, i thought i read about the pan keeping it in place is how it's designed.

You guys have given me a lot of great info and I really appreciate it. I'll get onto the PCM if the filter trick doesn't work, thanks Bob.

And rla2005 I'll check my wiring too. I've thought about just ordering a new harness at one point but could only find a used one on ebay for around $80. Anyone think that's worth a shot/ know of where to get a quality replacement let me know.

You guys are great! Cheers!