torque converter lock-up mod

[snatchal]

I read about a mod to manually lock up the torque converter on my E4OD POS, but I can't find the link now. Can anyone help me?
I am turning 2000 RPM at 55 MPH. When I first got the truck, I would have been turning about 1500.
If I push harder on the accelerator it feels like the converter locks and for a few seconds the RPMs drop, but then jump back up when the truck levels off.

 

[Mr_Roboto]

Quote:

For those who would like to convert there lockup to a manually controlled status via a two pole switch, the following will apply.
I post this information for people that do not want to entirely reverse engineer thier lockup circuit. Thus was the case on one of the vehicles brought to me. This mod was performed and works like a charm on an ambulance that had intermittent lockup problems. Intermittent lockup causes heat and convertor failure. Ideally in this situation the vehicle could be diagnosed by Ford with minor difficulty. However, it is my luck as is some of yours that the problem cannot be picked up by scanning the rig for faults. Poor grounds or dirty connections do not display themselves on scanners. This vehicle we worked on has a 9"x6" wiring harness in it. The process of reverse engineering that bad dog was unacceptable so we went to Ford. After shelling out big bux to Ford to say "we dont know where the problem is but we can keep working on it (for 65 per hour!)", we decided to mod the trans harness ourselves. You should have a multimeter available to you before performing this mod.

The E4OD in my opinion shifts like crap from the factory. lockup engages in all gears somewhat randomly and really gives unpredicatable results in shift feel. There is a solution but it is not for everyone. Several companies make trans command adapters which work nicely if everything in the vehicle is electrically tight. If there are connection problems in the vehicle regulating lockup circuit the trans controllers will not work. So the only other option in curing this problem of shift feel revolving around intermittent lockup and wiring problems is to install a manual switch to bypass the computer controlls for this circuit. DO NOT LET THE WIFE OR KIDS OPERATE THIS VEHICLE WITHOUT THIS SWITCHED MARKED "KEEP THIS SWITCH OFF." If this switch is left on below the speed of 25 the vehicle will shake and you may leave parts of your trans or engine behind!! This Switch cannot be placed in the "on" position until the vehicle speed is above 35 for most effective shift feel and control. For guys that want that control over shift feel this really does work great and should improve mileage for those who experience lockup cycling. Lets begin.

Identify the Main electronic harness going to the trans. Above the trans connector about 4-5 inches locate the Purple wire with a white or Yellow stripe on it. This wire gets stained with oil so look closely. Simply cutting this wire will make the trans shift through all the gear ranges except for convertor lockup. The trans will at this point shift better than you have ever felt before because the gear ratios are all nicely matched by ford. Early lockup screws up this nice ratio thus this fix will eleminate this.

Now that the lockup wire is cut attatch 2 lengths of wire to the two wires that are now available at the trans (one length per each lead).
drill a small hole in the floorboard under the carpet to get the two wires up to your dash somewhere convenient for a switch. At this point you need to do a test. Tie these two wires together. The trans should operate normally and lockup will come in as before you cut the wires. At this point all we created was a loop effectively lengthening the path of the convertor lock up circuit. Using your meter, and a second driver for the rig, get up to about 55 mph and hold steady. Set your meter to dc voltage on the 20 volt scale. Place your red lead to the two wires on your dash that are tied together and the black lead to the outer circle of your cigarette lighter (ground). At the speed of 55mph with the vehicle warm you should have a reading of about .5 to 3.0 volts. If you apply the brake and hold the speed at 55 you should see that voltage jump to 12-14 volts. If you let off the gas the voltage should be 12-14 volts. As you get back on the gas and return to 55 and level out you should see the voltage drop to .5-3.0 volts. With the vehicle in park the voltage should again be 12-14 volts. You will notice that when lockup engages the voltage drop occurs and lockup takes place. We are going to manually drop this voltage by adding a ground which is effectively what the computer does to engage lockup. If these results are not typical of your vehicle STOP HERE!! Your harness may be different and this Mod will not apply to your vehicle.

Assuming your tests indicated the correct results and you have the two wires inside your vehicle, open up the two wires you tied together and place the red lead on one of those wires and the black lead to the cigarette lighter outer ring (ground). You should notice that one lead will produce 12-14 volts with engine on and in park and one wire of the two will produce .5-3.0 volts when measureing to ground. Note the High voltage lead. Take your switch and place the high voltage lead reading 12-14 volts on one of the switches' poles and tighten it down. On the other side of the switch connect the remaining wire from the trans AND a jumper wire that is somewhere securely grounded to the chassis of the vehicle. This will in effect ground the second terminal to the chassis. The benefit of this arrangement will give the driver total control of lockup. Notice that when the switch is open (off) the computer cannot engage lockup if it is undesireable to the driver and around town you will get nice crisp shifts that contain nice ratios as designed by ford. Once this switch is activated lockup will engange and HOLD for the duration the switch is on.

I recommend you only use the switch for highway use to increase economy. That is unless your like me, I like the ability to control shift feel and it doesnt bother me to toggle that switch off and on for stops. If you're a control freak this is the nuts and works well. This mod was performed on a 91 Diesel ambulance converted to a service truck. As we have not tested it on all electrical configurations for each of the years we cannot assume that this mod will work in all applications. For those of you that it does work for, Enjoy....its a really nice feature that will payoff in economy. On the highway flip the switch and let her go!!! Even if you let off the gas a little, lockup won't fall out and then reengage like the factory controls. Once Boss Transmissions web site is back up we will provide schematics for those who would like to review the above procedure.

We make no claims about its intent or use. Perform at your own risk. Feel Free to correct anything I have said here. Read this Thread thoughly in case others experience situations that are undesireable. Thanks for your time..

 

[Mr_Roboto]

Now if we could figure out how to get this to work automatically, say once the trans is in 3rd or OD......

I have the same thing, an ambulance with intermittant lockup. I don't spend enough extended time on the highway for a plain switch to work.

 

[Ironman03R]

There are lockup controlers out there that do it automaticly, I know that Summit carries them. If your torque converter clutch material is all burnt up, like mine was, this mod will do nothing for you. I would be sure the trans is in good working order first.
After haveing my trans rebuilt, I gained 2mpg on the highway.

 

[argve]

In most cases the problem reverts back to the FIPL not being adjusted correctly or it's bad.

Now how to test/adjust the FIPL or TPS as it's called (Fuel Injection Position Level or Throttle Position Sensor).

Warm the engine to normal operation temps and shut down - leave key in the ON position with the engine NOT running.

Then grab your handy dandy Volt Meter and place the black probe on a solid ground - I like to use the neg battery terminal. Then take a paper clip or something that can reach in to a wire plug from the back side (side the wire enters) so that you can measure the voltage on the center wire on the FIPL which is mounted on the drivers side of the injection pump. You want to see somewhere between 0.9 volts to 1.2 volts on the center wire with the plug hooked up. If not then loosen the two or three bolts that hold the FIPL to the injection pump just slightly so that you can rotate the assembly then rotate until you get the required voltage. Now once you have it set - it touchy to get it correct and then check again after you tightened the mount back down. Now with the meter still connected actuate the throttle from one end to the other to check for smooth operation and also to see if the voltage swings smoothly throughout the movement.

What this FIPL does... It's nothing more than a potentiometer meaning it's a voltage divider - What happens is source voltage is applied across the device with the center wire being the wiper, the center wire is connected to the trans computer (yes even an IDI has a computer in it) when the computer sees the correct voltage on the center wire it knows how far you're pressing down on the throttle so that it can make the correct decision on how long to hold shifts, when to lock up the converter and what line pressures you need/require. If this is set incorrectly then all bets are off on what the performance of the E4OD will be.

Some say that you should replace the FIPL on a scheduled program like 60k Miles but what I found was that it would just simply rattle out of calibration from time to time and just needed to be reset to the correct position. Now I also found out by moving around within the 0.9~1.2 volt range that I could effec the "attitude" of the trans meaning how hard or smooth the shifts were and how long it would hold shifts out. I have always been a fan of crisp shifts and holding out the shift points a bit - if memory serves correclty you would set the voltage towards the upper ends instead of close to the 0.9 volts - but it's been a while since I have been under the hood of an IDI. Once set correctly you may rethink the addition of the manual lock up - I know that when mine was set correctly it would lock up in third gear and pretty much only unlock during shifts and when I pressed the throttle to the floor but would quickly lock back up. Now if I was buzzing along at say 70 mph and slipped the throttle the rest of the way to the floor the TC would NOT drop out of lock up - the truck would just speed up but if cruising along and snapped the throttle to the floor it would drop out of lock up then back into lock up.

Reason for setting the FIPL when the engine is warm is simple you don't want the high idle solenoid kicking the throttle up causing your measurements to not be accurate because as you accuate the throttle you will see that the voltage changes.

If the FIPL is out of adjustment just slightly you won't get a flashing OD light on the dash - which just so happens to double as a fault light - no it does not flash codes but if it's flashing it's complaining about something and you need to read the codes via a reader under the hood that you purchase from local auto parts store or take a stab in the dark at what's wrong. But if the FIPL is out of adjustment far enough it will send a fault code and cause the OD light to flash.

Now unhooking the battery cables and letting the truck sit does nothing for erasing the codes stored in the E4OD computer other than make you have to program in favorite radio stations and reset your clock. The computer does not "remember" codes on this vintage of software it forget them every single time the truck is powered down - got this from a member on STD that was on the engineering staff of the E4OD. Which my playing with the system on The Enterprise confirmed this - I like to double check my sources ya know... I'm just weird that way...

 

[snatchal]

Thanks Mr. R Thats the article that I was looking for.
I agree that this would be a perfect mod if there was away to make it unlock automatically below a certain speed.
I figure that if my tranny works OK after this mod then my problem is electrical, probably the stock computer. If that is the case then my next step is a Bauman computer. No use wasting money on another stocker.
If this does not help with lock-up problem, then it's probably time for a complete rebuild and a new converter.
By the way I have already replaced the MLPS, the speed sensor, the tach sensor, the RABs sensor on the rear pumpkin , and the FIPL.
If anyone has any other ideas, please chime in.

 

[yARIC008]

If you have an electrical problem, IE bad wires, then a new computer won't help at all. It'll still see the electrical signals going whack. I had for a long long time alot of problems with my transmission. I replaced the FIPL, tach sensor, speedo sensor, and readjusted the FIPL about 10 times before i decided i'd just replace the wires going to the FIPL because I seemed to be able to trace down my overdrive light blinking to them. When ever my OD light would blink, i'd just reach in and wiggle the wires and it'd stop putting the tranny in limp home mode for a couple days. So yeah, those wires turned out to be shot. Replaced those wires with nice shielded ones and haven't had an ounce of trouble since.

My T/C would lock and unlock all the time too...

Anyways, what i'm saying is that it's not your stock computer that's making things go funky, it's wiring or a sensor. Look for any chaffing or smooshed wires. Replace anything that even looks kinda questionable. Unless your tranny fluid smells burnt, i doubt your T/C is causing the problems. But, excessive locking and unlocking may cause it go destory itself.

Here is a little schematic I made a while back for wiring up the manual lock. In this setup you can have two switches that allows you to let the computer control the lockup or you do.

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[Mr_Roboto]

Thanks for the post argve. I never understood what "backprobing" meant till now.

I keep wanting to check the FIPL sensor on my van, but things are so darn hard to reach (and fuel filter is right there too). Hopefully with your instructions and an alligator clip I can get it done. I'd be in heaven if my lockup worked right.

 

[yARIC008]

Thanks for the post argve. I never understood what "backprobing" meant till now.

I keep wanting to check the FIPL sensor on my van, but things are so darn hard to reach (and fuel filter is right there too). Hopefully with your instructions and an alligator clip I can get it done. I'd be in heaven if my lockup worked right.

Ah yes, can't even see it on the van, lol. I have to remove my fuel filter assembly to work on it. Just can't do it any other way. Unless of course i remove the A/C compressor... but i take my chances with the fuel filter

 

[snatchal]

In most cases the problem reverts back to the FIPL not being adjusted correctly or it's bad.

I have replaced the FIPL and adjusted to specs. No difference. I have also tried setting it lower than specs and higher than specs. Still won"t stay locked up. I just think that doing the lock-up mod is a cheap way to narrow down the problem.

If you have an electrical problem, IE bad wires, then a new computer won't help at all. It'll still see the electrical signals going whack.

Yes, electrical gremlins are the worst to find. I've been fighting with this thing since last fall. Drove it in limp mode for two weeks before I found part of the problem. I had two bad grounds and a rotted out connector on the voltage regulator. Also had no power at the computer relay. That turned out to be a couple fried fusible links.
I probably did some mechanical damage by driving in limp mode and will have to have the tranny rebuilt, but I want to make sure that it is not electrical first. I tried to get a new wiring harness at the dealership but no go.

 

[Mr_Roboto]

Ah yes, can't even see it on the van, lol. I have to remove my fuel filter assembly to work on it. Just can't do it any other way. Unless of course i remove the A/C compressor... but i take my chances with the fuel filter

Well I long ago pitched that stupid plastic air intake (the one that is crimped to half diameter to clearance the upper radiator hose) so I can actually see the stuff on my van motor. I should be able to use a large screwdriver to pry up the clip on the FIPL sensor wire and I can get my hand in there to pull it off. Now getting to the FIPL sensor screws is another question. I can see one, the others will be by braile.

 

[Mr_Roboto]

I was thinking about the mod. The above procedure disables normal operation of the TCC. By using a double pole (ON-OFF-ON) switch, you could wire it for normal operation, TCC disabled, or TCC manual lock.

The switch is available at Radio Shack, in the "toggle switch" drawers. Since it's made for AC current, you have two seperate sides. I used the same switch to switch both + and ground to make a combination GP and RUN switch for my ambulance.

Wire the switch for manual lockup in up position, lockup disabled in middle position, normal lockup in down position.

 

[snatchal]

I just got done doing the converter lock-up mod. It works great, just as Mr. Roboto's instructions described it. With the switch off it shifts through the gears smoother than it ever has before, just no lock-up. Flip the switch at highway speeds and I can feel it lock up and the RPMs drop about 300-400.
This is telling me that my problems are all electrical. I am going to run it like this for a couple weeks just to make sure that this is going to work. Then I am going to buy a Bauman computer. I don't want to use it forever with just the switch because as stated in the article if you don't turn it off before slowing down you WILL break something.
Of coarse I had to try it at low speed. (I've always had to learn everything the hard way. I guess it's the Swede in me ) At low speed the truck bucks just like a standard if you don't push in the clutch when coming to a stop.

 

[yARIC008]

I just got done doing the converter lock-up mod. It works great, just as Mr. Roboto's instructions described it. With the switch off it shifts through the gears smoother than it ever has before, just no lock-up. Flip the switch at highway speeds and I can feel it lock up and the RPMs drop about 300-400.
This is telling me that my problems are all electrical. I am going to run it like this for a couple weeks just to make sure that this is going to work. Then I am going to buy a Bauman computer. I don't want to use it forever with just the switch because as stated in the article if you don't turn it off before slowing down you WILL break something.
Of coarse I had to try it at low speed. (I've always had to learn everything the hard way. I guess it's the Swede in me ) At low speed the truck bucks just like a standard if you don't push in the clutch when coming to a stop.

I ran it for a long while. I only left it on coming to a stop 2 or 3 times... never broke anything. Stalled it once i believe.

 

[norve8c9]

Ya, I did the mod last night, works great. Hopefully a couple more MPG's will be coming my way now.