Do v8 models have torque converter lock up solenoid ? | Ford Explorer Forums - Serious Explorations

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Do v8 models have torque converter lock up solenoid ?

Explorer_PL

Explorer Addict
Joined
November 16, 2007
Messages
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City, State
Rockland County, NY
Year, Model & Trim Level
06EB V8
Last Friday, my 06 v8 stalled on me twice. First time when I was taking a wide turn from Rt 80 into Garden State Pkwy and had to abruptly slow down/stop with my wheel turned (so power steering pump was under load if that matters). I quickly shifted to N and restarted with no problems.
Then, when I was backing in to my driveway, wheels straight, foot on the brake going downhill it did it again..

I had a similar issue when the car had 200k miles, and it turned out it was a torque converter staying locked up and stalling the motor. I replace the TC with a Ford unit and all was good for 70k miles. I would not think the "new" TC is already toasted. Is there a solenoid controlling that or that's part of the transmission control module ?

Thanks all.
 



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Sorry I’ve got no insight into your problem, but it’s nice to know you passed within a half mile of my house!
Especially if you went home the same way...once u take the ramp from 80 onto parkway north, as soon as you go thru that toll both, I’m off to the right thru the trees!
 






Small world Mike :)
After I read my post, I realized i had it wrong. It happened when going from Southbound GSP to Rt 80, right after you pass the UPS. That's the long curve going towards NYC.
But I go thru the tolls on 159 daily when going home to Rockland, and you are probably one of those houses with the beautiful Holiday lights in December, on the right hand side going North on GSP.
 






I had the same problem with my torque converter, but when the converter failed it sent metal shavings all through the trans and ruined it. Had to replace the trans and converter too.. the TCC lockup solenoid is on the mechatronic unit but I doubt the solenoid is bad, hope it is not another bad converter! I wonder if there are updated part numbers or redesigned/upgraded torque converters we can use for our trucks...
 






When my failed, I went to Ford and bought OEM replacement. I did not go for some cheap eBay unit especially since Ford one cost around $ 300.
Of course there are no error codes stored, and I am waiting for it to happen again. I am trying to "provoke" the car to do it and so far no luck.
I have been getting some misfires and bucking for a while, but waiting for the 30x code to pop up to replace the coil or spark plug.
I replaced the mechatronic at around 214k miles so they have maybe only 60k miles on them.
 






A small update.
Finally, I got a 0354 on my way to work. I had the engine kicking and bucking for a while, but no code.
Now, I know # 4 coil is bad.
I hope it cures the problem because the TCM harness runs on top of #4.
Few years ago, my #3 and 4 were bad, and when a coil is bad it interferes with that harness and messes up the signal going from the PCM under the hood to the TCM in the transmission., so I hope that will solve the stalling issues as well.
Tonight, when I get home, I'll swap the coil with some spares I have in my garage.
 






I hope that is all it is. Isn’t it amazing how much you’ve learned about that truck over the last few years.
 






@Explorer_PL To answer your OP question easily, yes, Torque Converter Clutches became pretty common by the early to mid '90s, in almost all vehicles, Ford included. AFAIK, they all are engaged/disengaged by use of an electrical solenoid, which pushes a little valve in the transmission's valve body, shunting fluid pressure on and off to the TCC.

A failed "ON" TCC will stall the engine upon trying to make the vehicle stand still in any gear. Just like an old fashioned clutch, don't release it, engine is "killed" at the stop sign. Failed "ON" may be mechanical, due to the clutch itself (ouch!), or electrical, the solenoid failed, either mechanically or electrically (mine failed mechanically, it's guide bushing around the plunger crumbled to pieces).

Failed "OFF", that is, TCC disengaged, affects only fuel economy, unless the TCC itself has generated metal shavings in the TC, which will kill the transmission. If failed off is due to an inoperative TCC solenoid, you can drive the vehicle forever as it is, if you can bear the Check Engine Light always ON, or the OD OFF light flashing, or both. imp
 






Imp -

thanks for the detail explanation. Just a small update, last night driving home it stalled again last night coming down a hill, when I braked heavily, and taking a turn at the same time.
Then at night I swapped the coil # 4, I was tempted to change the spark plug as well, especially since I found brand new one still in the box, but I was too lazy at 9 PM.
So this morning on my way to work, it kicked and bucked again just a little but enough for me to notice. In the past, I would at this point replace all coils and sparkplugs, but somehow I do not feel like spending about $ 400 on Motorcraft parts.

When my first torque converter locked up for good after 200k miles, the tech at the Ford hooked up the car to their diagnostic unit and was trying to trigger the lock up and release condition. The way I understood it, the signal was being sent so the electronics were ok, but mechanicaly the TC would not unlock. It was cooked :) He also showed me printouts of graphs showing RPMs at the tranny and the crankshaft, and they were all in "sync" when they should not have been. The engine should have had some RPMs when the tranny should have been at "rest" but it was coupled constantly.

Well, I wonder if the "stall" incidents are stored anywhere. Otherwise, I need to wait till it gets more frequent and I can reproduce it on demand.
The last thing is I do not want to pay for diagnostic time only not to be able to reproduce the condition.

Stay tuned.
 






Imp -

thanks for the detail explanation. Just a small update, last night driving home it stalled again last night coming down a hill, when I braked heavily, and taking a turn at the same time.
Then at night I swapped the coil # 4, I was tempted to change the spark plug as well, especially since I found brand new one still in the box, but I was too lazy at 9 PM.
So this morning on my way to work, it kicked and bucked again just a little but enough for me to notice. In the past, I would at this point replace all coils and sparkplugs, but somehow I do not feel like spending about $ 400 on Motorcraft parts.

When my first torque converter locked up for good after 200k miles, the tech at the Ford hooked up the car to their diagnostic unit and was trying to trigger the lock up and release condition. The way I understood it, the signal was being sent so the electronics were ok, but mechanicaly the TC would not unlock. It was cooked :) He also showed me printouts of graphs showing RPMs at the tranny and the crankshaft, and they were all in "sync" when they should not have been. The engine should have had some RPMs when the tranny should have been at "rest" but it was coupled constantly.

Well, I wonder if the "stall" incidents are stored anywhere. Otherwise, I need to wait till it gets more frequent and I can reproduce it on demand.
The last thing is I do not want to pay for diagnostic time only not to be able to reproduce the condition.

Stay tuned.
@Explorer_PL
Given a TCC engaged, locked all the time, in order for it to stall the engine, the wheels and driveline must come to a near-standstill, where eng. rpms drop below normal idle speed. OTOH, the vehicle will continue to move with locked TCC at idle speed, creeping along, unless you slow it to near-stop. Therefore, a stall while coasting say downhill under any circumstances with locked TCC will be due to some other cause, imp
 






Hmmm...
That maybe a good news, I thought I was going to have to drop the tranny and with the weather getting cold here on East coast, that was not a pleasant perspective.
I know that this TC is not locked all the time, I thought that it does not unlock in situations when it should - like braking or slowing down, where pressing the brake pedal should send the signal to disengage.
The previous TC was LOCKED, and I mean it. I would start the car, put in in D and would have to use a lot of force to press the brake, and the car would still creep forward, or start shaking and the engine would die.

This is different. 99% all is fine, just those single occasions when it stalled got me puzzled.

PS: Just replaced the plug and compared the tip to the new one I had. The electrode was very short so the gap was big compared to the new one. If that's how all the other 7 look like, maybe I need new ignition components.
PS2; Few weeks ago I cleaned the TB so that was taken care of.
 






Hmmm...
That maybe a good news, I thought I was going to have to drop the tranny and with the weather getting cold here on East coast, that was not a pleasant perspective.
I know that this TC is not locked all the time, I thought that it does not unlock in situations when it should - like braking or slowing down, where pressing the brake pedal should send the signal to disengage.
The previous TC was LOCKED, and I mean it. I would start the car, put in in D and would have to use a lot of force to press the brake, and the car would still creep forward, or start shaking and the engine would die.

This is different. 99% all is fine, just those single occasions when it stalled got me puzzled.

PS: Just replaced the plug and compared the tip to the new one I had. The electrode was very short so the gap was big compared to the new one. If that's how all the other 7 look like, maybe I need new ignition components.
PS2; Few weeks ago I cleaned the TB so that was taken care of.
@Explorer_PL

Ford programs it's TCC through the gas pedal, among other inputs, but important thing to know is that, cruising at speed, constant throttle, if you release gas pedal, TCC immediately disengages. If you press pedal back down to cruise position, TCC re-engages. So the driver who constantly presses and releases his gas pedal on the highway when unnecessary is killing his TCC system prematurely. First solenoid to die, usually, TCC. imp
 






@Explorer_PL

Ford programs it's TCC through the gas pedal, among other inputs, but important thing to know is that, cruising at speed, constant throttle, if you release gas pedal, TCC immediately disengages. If you press pedal back down to cruise position, TCC re-engages. So the driver who constantly presses and releases his gas pedal on the highway when unnecessary is killing his TCC system prematurely. First solenoid to die, usually, TCC. imp

Hey imp. :wave:

What do you suggest for people who drive rural roads at 55mph where the TCC is constantly engaging and disengaging when tip-toeing the throttle due to traffic, road conditions and ever changing slopes in hilly terrain?
 






Hey imp. :wave:

What do you suggest for people who drive rural roads at 55mph where the TCC is constantly engaging and disengaging when tip-toeing the throttle due to traffic, road conditions and ever changing slopes in hilly terrain?
@Centaurus5.0
First, you must release gas pedal suddenly and completely to ensure an unlock. Gradually easing off, but not very much, will not unlock and allow the vehicle to slow down, but not a quick slowdown. By practicing observing your tachometer, you can tell whether the TCC has unlocked or not. Ford locks the TCC in most models, when accelerating moderately up to cruise, as the last input after all shifts are completed. I have a 2004, 5-speed auto. First drop downward on tach is 1st to 2nd gear, second drop 2-3, etc. until after the 4th. drop, which is 5th gear, OD, soon the tach will slowly, with constant gas pedal, drop a couple hundred rpms; as the TCC is locked. You can confirm that by very slightly increasing gas pedal----the tach will not go up. Push it more, and the tach will jump up, and the TCC is unlocked. Then, increasing gas jumps tach even higher. That happens any time the TCC is not locked or engaged, call it what you will.

One reason Ford disengages the TCC with throttle turn off is for hill-holding engine braking, which is greater with the TC in play. I see no real reason, personally, to program where TCC must constantly be locking and unlocking, thought about installing a manual switch, normal driving, reach 3rd. or 4th, turn the damn clutch on! But, that'll throw a CEL, so I haven't done it.

As an aside, the old AOD was a first step toward a TCC, which it did NOT have (was not electronic). Had two input shafts going into the trans, running coaxially (one within the other). The second shaft connected directly with the 3rd. gear planetary, and it was driven with the converter housing, IOW, by the engine, thereby bypassing the converter. So AOD had NO TORQUE CONVERTER action in 3rd. or 4th. gears. 4th. was overdriven. Lots of folks don't know about that. imp
 






An update -

About a week ago I installed a set of 8 new Motorcraft coils and plugs, total was $ 250.
I drove several hundred miles since then and the truck runs like new, no bucking, kicking or hesitation going uphill. Also, it has not stalled again.
I hope it does not stall again and if it does not in the next few weeks, it would be super interesting how much the ignition system affects the engine operations.
 






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