Kracker1019

I have a 1994 F150 4x4 5.8L with an E40D transmission. I just bought this truck for my daughter so still learning about it. I have done the basics i.e. tune up, clean throttle body, check firing order is correct. The engine runs well (slightly high idle) but when I put the truck into gear and apply the slightest throttle the truck will shake with much vigor (shakes the entire cab) and has almost no go at all and I mean barely a crawl. The O/D is flashing and working on pulling the codes which I presume will tell me the torque converter is bad (by the symptom). I am wondering is there anything else that can cause this problem? I can rev the engine in park and neutral without an issue, when put in reverse/drive it seems to clunk but in reverse is doesn't buck. I have check the fluid level and it is spot on (just replaced the filter and fluid however didn't drain the TC not sure if that's even possible with out removing it). I would like to exhaust all my options before I pull this transmission. Any advice or assistance would be greatly appreciated.

Steve83

No, codes do NOT tell you what part to replace. They only suggest where to BEGIN diagnosis. Click these & read the captions:


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If you suspect a transmission problem, read this caption so you understand how it works:


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But there is no torque converter fault that can cause any lights to flash. The TC is not electronic. It's more likely an ignition system fault. To understand & diagnose that system, read these:


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These describe other known problems that could affect that truck:


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Steve83

Only 10 images allowed per post...


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Kracker1019

This is great information! I am pulling codes this evening. The gentleman that owned it before me put a push button start on the truck for some unknown reason. The truck starts fine could that be affecting anything? He also removed the A/C compressor and replace with a bracket and pulley. The electrical connections are just tied out of the way I read on one of the above that has an effect on the transmission? I also found out that the transmission is out of a '95 F250 could this be affecting the PCM? it has all the right connections

Kracker1019

So pulled the KOEO codes and from what I have read I need to fix these first.

638 - trans fluid temp circuit below minimum voltage
654 - trans range sensor (mlps bad or out of adjustment)
621 - shift solenoid 1 failure
629 - torque converter solenoid failure
626 - coast clutch solenoid failure
624 - electronic pressure control circuit failure

For continuous codes I got

512 - eec processor keep alive memory failed

So for the mlps I am goin to adjust it first to make sure it's right. Does anyone know how to test the solenoid pack in the transmission or is it better to just replace since so many failures there? So when I changed the trans fluid and checked the pan nothing smelled burnt and no major gunk or shavings. Any suggestions on where to start first?

Steve83

Usually for a mechanical problem inside the steering column.


(phone app link)Butchered wiring? Of course it could affect how the truck runs.How exactly did you identify that?Not really, but the EEC may not be built to control that trans, which might be the source of the vibration.Ford only uses so many connector shapes, and they frequently re-use one shape even when it's wired or pinned differently and is INcompatible. IOW: wrong things will still plug together.Actually, you need to DIAGNOSE them first.NO. Re-read the first line of my first reply above.Start by putting ALL your truck's details into your signature so we don't have to keep digging back through the thread to see if/where you posted them. They need to be visible with EACH of your posts. Read the caption of the 3rd thumbnail in my first reply above.

The first step in diagnosing any code is to confirm that the indicated condition actually exists. For example: 638
- IS the TFT voltage too low? Is it because of some electronic fault, or is it because the fluid temperature is outside the self-test range? Did you read & follow all the self-test instructions, including warming up the engine first?

But the highest-priority code in your list is the last one. If the EEC memory has actually failed, then NONE of the other fault codes in the EEC can be trusted. Now that you've read & recorded the fault codes, clear them (the correct way) and re-check them frequently. See how long it takes for 512 to re-appear. If it comes back instantly after clearing codes, then it's probably accurate, and the EEC is dying. There's no point doing ANY OTHER diagnosis of the fault codes or driveability until 512 is correctly repaired.