Ford Power Stroke Nation banner

1 - 12 of 12 Posts

·
Registered
Joined
·
600 Posts
Discussion Starter #1
Yesterday my converter stopped locking up. Took it to a trusted trans shop and hooked up a SnapOn Scanner. The truck is throwing no codes, but in real lime logging, the ecm is commanding the converter to lock. Since the ecm is commanding it, and there is no codes being set, does that mean the converter is getting the message and locks but it’s just slipping and therefore the ecm can’t detect the mechanical failure? I have been getting the code for converter lockup failure off and on for the past year. It would set the code but it still locked up fine.
 

·
Registered
Joined
·
3,676 Posts
I would look at wiring before jumping to worst case scenario. Lol

Sent from my SM-N960U using Tapatalk
 

·
Registered
Joined
·
600 Posts
Discussion Starter #3
We looked at that yesterday and it all looked good visually. That would be the harness going to the trans correct? Funny thing is, when going down a slight decline or perfectly flat ground, it feels like it locks. 2600 rpm @ 70 mph when going up an incline, 2100 when on flat surface or slight decline. Accelerate just slightly, and it jumps right back to 2600. Is it possible to just partially work?
 

·
College Student
Joined
·
191 Posts
Whats the tranny fluid color on the dip stick?
 

·
Registered
Joined
·
600 Posts
Discussion Starter #5
Looks new, smells new. Its 6 months old.
 

·
Former Ford Trans Engr.
Joined
·
3,043 Posts
Since the ecm is commanding it, and there is no codes being set, does that mean the converter is getting the message and locks but it’s just slipping and therefore the ecm can’t detect the mechanical failure? I have been getting the code for converter lockup failure off and on for the past year. It would set the code but it still locked up fine.
The PCM can detect a mechanical failure. You were getting the code, it just hasn't set again, yet.

What does the front face of the torque converter look like? When the converter clutch slips it heats up the front of the converter, which will blue it, similar to a gun that has been blued.

We looked at that yesterday and it all looked good visually.
A visual inspection only finds the most obvious problems. A bad harness usually looks fine.

Having said that, the electrical tests that look for opens and shorts in the wiring harness are the most robust tests the PCM runs. If there were an electrical problem there would be a code for that.

Funny thing is, when going down a slight decline or perfectly flat ground, it feels like it locks. 2600 rpm @ 70 mph when going up an incline, 2100 when on flat surface or slight decline. Accelerate just slightly, and it jumps right back to 2600. Is it possible to just partially work?
Yes, it is. That would cause the front face of the torque converter to turn blue.
 

·
Registered
Joined
·
600 Posts
Discussion Starter #7
I drove the truck all day today and no converter lockup, and no codes thrown. Perhaps it’s just complete coincidence, but this evening I looked under the hood and the vacuum line to my map sensor had blown off. I reattached it and installed a hose clamp. Now the lockup is working again! Wtf???
 

·
Registered
Joined
·
600 Posts
Discussion Starter #8
By front face of the converter, it that the side that faces the trans?
 

·
Registered
Joined
·
600 Posts
Discussion Starter #9
Do I even need a triple disk billet or a single disk billet ok? Daily driver truck in sig.
 

·
Registered
Joined
·
3,351 Posts
Check the 3rd brake light on the cab and your rear brake/tail lights. 3rd brake light and rear brake lights not working can cause issues with TC lock up as I recall. Ensure they are working correctly.
j
 

·
Registered
Joined
·
600 Posts
Discussion Starter #12
Face of the converter looks good, but I’m going to replace it.
 
1 - 12 of 12 Posts
Top