I would listen to Bluegrass he is very knowledgeable on this subject. My dads 98 with a 4.6 had the same issue. We all thought that the tranny was going. After i found bluegrasses posts on here we put on a new coil at 170,000, the tranny felt great and the truck ran like new, it now has 187,000 on it and going strong.

This shows what great help FORDTRUCKS can be!

 

Take a look at the thread title 'strange misfire problem'.
This is often misconstrued as a transmission trouble.
The hint is how it acts.
Transmission faults usually don't act the same way.
Good luck..

 

I finally got some time off and good weather at the same time. So today I replaced everything from the spark plugs to the distributor and coil. As I stated in a previous post new distributor. All new parts. Still have the problem between 40-50 mph under light acceleration in overdrive only. I thought it might be a crossfire problem but I followed the plug wire routing per the manual so it wouldn't crossfire. I made sure the plug wires were not touching any steel brackets.

Autolite plugs gapped @ .054
Autolite Professional plug wires
MSD Coil and cap

I think it could be in the trans. I think I will take it to the Ford dealer for a fluid and filter change.

 

Did some more digging into posts and found this one https://www.ford-trucks.com/forums/1...crossfire.html with a tip to take the #8 plug wire out of the loom to eliminate crossfire. I did this and double checked the rest of the plug wires. I re-routed the wires from #1 to #4 slightly to have them go under the EGR tube instead of over the tube. Most of the misfire is gone on my first test drive. Still a little roughness but much better.

 

I have the same shudder but under very slight acceleration ( doesnt always happen ) . Only at 40 or 45 mph. Brand new msd 8.8 wires, an new plugs.

 

When changing the fluid in a 2001 2WD with 4R70W transmission [which was shuddering], I found this in the oil pan. Does anyone recognize what this is. I did not see it on the schematics I could find and wondered if it could contribute to the problem

 

This is the peri stallion plug at the dip stick port. It is pushed into the trany pan when the dip stick is installed during truck assembly.

 

Misfires only in OD at light throttle:
.
In OD the EGR is called to open allowing exhaust gas to flow into the intake tract, by design.
The purpose is to lower combustion chamber temperatures.
This action advances the ignition timing and reduces fuel injection amounts.
The results of this action is a very LEAN condition.
The Lean condition needs an ignition system in good condition due to the higher voltages required to fire the Lean mixture condition.
If any cylinder falls short on voltage, misfire will result under these specific conditions.
When the EGR closes from down shifting the EGR closes and conditions return back to lower voltages required to fire the standard mixture ratios.
Best way to find an offending coil is to look at stored data under mode 6, test 53.
This stored data is the misfire counts for each cylinder.
If any cylinder has high counts it likely is a cause of misfire and will not set a code.
The reason is the condition comes and goes with the driving condition so is actually cancelled as a possible code set due to it not being a 'hard' fault.
Bottom line is, do the testing before replacing parts.
Good luck.



]

 

Thanks for the answer!

 

Pretty much 99% of the time its coils. been there with my 2001. Ive replaced 7 of my coils. by watching the tach, I can see when lock up occurs. never have a TC shudder. I can feel the difference. I also have a transgo shift kit as well.

 

Hey guys so i recently flushed my trans out. (Minus torque converter) as my Mechanic didnt think iy was necessary. And changed my trans filter as well. How quickly should i notice a change in the trans preformance. As my trans still wants to shudder.

 

Because it's not the transmission that causes the shudder.

 

Ok so i absolutely need to drain my torque converter then? So my delima is. I put gobs of new fluid into it. But never completly cycled out all the fluid from what im understanding. Could i just flush the torque converter and use some new mercron v? I put the shudder fix into the trans? Is that going to be an issue? Im confused as to how to use the shudder fix but its already being circulated into the trans.

 

You have not paid attention to the help in this thread.
You have a faulty ignition coil.
Use a Scanner to look at mode 6, test 53 for the cylinder with the high misfire counts.
Good luck.

 

Sorry ive got a bunch of stuff running through my head. Ok thank you very much!. Ill definitely use this to help me with mt problem thank you for the quick replies.