Hello Everyone,

Well, I'm still dealing with the same issue from many, many years ago. I refuse to give up -- I want to solve it, darn it! And I hope y'all can help.

Many years ago my Expy started acting up. Started misfiring, became very hard to drive. I brought it in and was told the "finger-followers" broke and made a mess. The mechanic could fix it but it would cost about the same to put in a remanned long block. So, I elected to go with the long block from Promar.

Long block in and the problem was better for a while after a few more trips back to the shop to have them fix various areas they screwed up on. Long story short, the mechanic that worked on my truck was a thieving idiot but the place came recommended by someone who had a lot of work done in the past by them. Apparently not by this specific mechanic though. But anyways...

Since then I've been dealing with the same issues. The truck feels like it is misfiring. It shudders and shakes under any light load and gradually gets worse as the engine warms up. Notice I said 'feels like it is misfiring'. I've replaced all the COPs (twice, generic the first time, Motorcraft the second), the plugs (multiple times with recommended Motorcraft plugs), and the injectors (plus a lot more parts that I'll detail below).

I've hooked up OBDWiz and pulled the Mode 6 test data for the cylinders and it shows ZERO misfires for all cylinders, no matter how hard I drive it. On a side note, when I pull up the test data in the console, it shows 10? cylinders vs 8? I'm not sure what the last two are (09 and 0A I think). I'm assuming that 01-08 are the ones I'm concerned with though. I can provide a screenshot of this data (or any other data that is requested).

So, at this point, no codes, no misfires, and still stumbling and shaking like all hell at times. It does feel like a back and forth hard shake at times. Almost as if the entire exhaust or drive shaft is jerking forward and backwards. That doesn't happen all the time.

The shaking and shuddering happens more at lower rpms (generally around 1500) and all speeds. At higher RPMs it seems like it smooths out until it shifts and the RPMs drop, then it shakes and shudders.

Engine Stalling at Stop - This is a new symptom. Now, this started a few days ago after I replaced the DPFE, Throttle Position Sensor, and the EGR Valve. The engine will stall out when coming to a stop in drive or reverse but not in park or neutral (as if the torque converter is locked out). I'm not sure if it is absolute coincidence that this happened on the drive I took right after replacing those three items or if they are some how related. I'm hoping that this symptom, along with the replacement of those items, will provide enough information for someone to have something to point at or check.

I've also replaced the EGR Vacuum Solenoid Valve but that didn't change anything. I don't mind replacing almost 20 year old sensors that are fairly cheap, even if they don't solve the issue, because I assume most of them are past their life-span and probably are not operating at near optimal performance any longer. I'm not willing to replace a $100+ part on a whim though.

I did find two holes in the exhaust, one just before the cat on the drivers side. Looks like it is at a joint and on the very top where welding it is impossible without dropping the exhaust. I've tried to seal that up the best I can as a temporary fix. The other one was tiny and easy to fix and near the muffler. I suspect there might be a few more but I need to go out and check now that those two are sealed up.

A long time ago I had the wiring harness (on the passenger side) melt when it came into contact with the exhaust manifold. I carefully went through all the wires in that area and fixed them up and have secured the harness in a location that it can't happen again.

I checked pin 54 on the PCM plug, using a small light, to see if there were any shorts in the line (negative into the 54 hole on the plug, positive to the battery). No light. I read that someone else used this test to find a short in the wire. I'm not even sure if it is pin 54, but any PCM pinout that I can find, shows 54 as the one that goes to the TCC solenoid. I've just been unable to verify it for my particular model.

Last night I dropped the tranmission pan and drained the torque converter overnight. The pan was very clean. The magnet had some sludge on it but that is expected. No other shavings, parts, pieces, etc that I could find. The fluid is bright red (I got up close and personal with it when the filter slipped out of my hand). It doesn't smell burnt or anything (not that I'm exactly sure what it would smell like but I assume if it were burnt it would be pretty obvious). Several years ago I dropped the pan (prior to the engine swap) and replaced the approximately 7 quarts and the filter. That was back in 2008 I think. I'm not sure if the transmission has ever been completely drained. I know that I never have since I bought the truck back in 2005.

Before I replace the plan and fluid though, I'd like to know if there is anything I should look at, test, possibly replace. I know somewhere there is a TCC Solenoid and (apparently) a wiring harness, that can cause these issues. I don't even want to think about replacing the whole valve body or torque converter unless I can absolutely prove that one or the other is the issue. I can do a lot of work myself but replacing the converter is not something I'm going to even consider or attempt while laying on my back. Plus, I don't have any real transmission experience past what I've outlined here.

I'm sure I've missed a bunch of stuff that I've done but please, please ask if you think of something. I'm willing to test and try just about anything at this point.

I really appreciate it that you've taken the time to read this post to this point. I know it is long but I wanted to provide all the information I could remember. I'm hoping someone has an idea.

Thank you again!
Jess

 

Here is a link to a much older thread I posted back in 2010 when I was fighting with the issues (just before the engine swap). There is more information in there that may or may not be relevant.

https://www.ford-trucks.com/forums/1...ndrivable.html

Thanks!

 

You've done so much it's kind of hard to recommend anything at this point. I'd say the easiest thing left for you to try is a bottle of Lucas Transmission fix to see if it clears up the shuddering. I know it worked for me with a Mustang I used to own.

Transmission Fix

 

Considering that the engine is new, and has no codes and you never stall in Park or Neutral, have you considered that it may be an issue with the transmission? Could be only the TCC, but who knows if there's any other issues in the transmission itself? If the Lucas Transmission Fix doesn't help, perhaps you could bring it to a reputable transmission shop and have them diagnose the transmission, i.e. check for codes in the transmission and test drive. If you have a OBDLink scanner, try FORScan to see if you can see codes for other modules, it's more specific to Ford vehicles and can read codes that the standard OBDWiz app can't.

FORScan

 

Yeah, I have FORScan. I'll have to give that a try again once I have it back up and running.

At this point I'm suspecting it has something to do with the transmission and/or wiring but I'd like to narrow it down to the actual issue if possible. I was hoping there would be a way to test some of the parts and maybe eliminate what it is not. Unfortunately it seems that transmissions are a magical, mystical area that very few people understand

I might have to see if I can find a reputable transmission shop around here to eyeball it.

 

Well, transmissions are a complex thing, but it's not that difficult to get into them. There are a few service manuals on the transmission out there, the issue is that most of the work requires the transmission to be taken out, and then it usually makes more sense to just rebuild it while you're at it. But, it should always be properly diagnosed first so you don't throw money at the wrong thing, and an expert on transmissions would be the right person to do just that.

 

New Symptom:

After draining the tranny and torque converter (about 15 qts total), I refilled it today. Started the truck, and it screamed bloody murder. I let it run for a few seconds, thinking maybe the fluid had to circulate back through the system. It didn't stop so I shut it off. Waited, started it back up for a few seconds. Same thing. Listened under the truck and could tell it was coming from the tranny. It sounds like metal on metal. Shut it off again.

I also noticed that the fluid level on the dipstick never went down.

Is it possible that this whole time I've had a bad pump that wasn't circulating the fluid? Thus, it was getting hot and having all sorts of issues?

 

If the pump wasn't working as it should, I'd expect to see some metal shavings in the pan. But it sounds like you need a new transmission for it.

 

I've had very similar issues over the years with my 1999 expedition 5.4.

It's always be some combination of ignition coils and the vacuum hose that goes from the EGR valve to the rear of the intake manifold.

Mine was shuddering and running poorly last week, I replaced all 8 ignition coils and it runs great now.

I had to replace the vacuum hose at least 3 times over the years, when it goes bad it's hard to keep the engine running.

 

UNCatTech - I've had to do the same thing over the years and that sometimes clears up the issue. The problem now though, is that the engine sounds great but the transmission sounds like metal on metal.

I don't know much about transmissions, but if the vehicle is in park, what is moving/spinning?

 

From your description I'd have to say that the pickup tube seal isn't in there and the pump is sucking up air instead of fluid.