Thanks 1995XLT for the help. I am going to try wiping the vss and if that isn't it replace the transmission range sensor. Sometimes the reverse lights do not work so perhaps it is time to replace anyways.

 

So finally an update.
I got a new Ford Transmission Range Sensor and installed it. I made sure to have the tranny in neutral and align the mark on the sensor. No sweat. No change either. Reverse lights work better. The shifter does feel nicer shifting into the gears but no change in the issue. I also pulled the VSS. There was a lot of shavings on it so I cleaned it off, checked the wiring, reinstalled with some dielectric grease. No change. So now after searching around some more I will check into the connector on the Passenger side of the transmission to see what that looks like. I also want to pull codes again. I have been shifting the transmission myself though the gears and the truck drives just fine. So I am wondering about the shift solenoids. I did have the fluid changed, filter changed and a flush done on it a few months before all this nonsense started so I am wondering if perhaps any debris was moved and now gets stuck in those solenoids or something like that. It didn't look bad when I was in there at the time, Fluid looked fine no burnt smell. The only thing else is the MAP sensor.
Anyone feel free to chime in. All the searches I have done seems to point to the solenoid pack. I do have 200,700 miles now and this is the only issue. I would be ecstatic to get this fixed.
Thanks

 

You still haven't changed the MAP sensor?

 

No. I don't know if that is at fault. The engine runs just fine. It is the shift scheduling that is at fault. The transmission will not shift gears on its own. If I shift it from 1 to 2 to drive to overdrive the truck runs great. No surging or anything. That is why I thought the transmission range sensor was at fault plus the fact that shift was sloppy and reverse lights would work every once in a while.
How do you test a MAP sensor? Im not about just throwing parts at a problem hoping to fix it.

 

http://troubleshootmyvehicle.com/for...e-map-sensor-1

http://easyautodiagnostics.com/ford/...sensor-tests-1

 

thanks GLC for the websites. I think there may be a multimeter that tests hertz here at work. Just need to find it.
Thats great. I will see what happens next.

 

Now at I am back in country, I have taken up the troubleshooting to this issue. I was able to test the MAP sensor using a Fluke with HZ capability. That was fine. So I went back to pulling codes. The only thing I get is the same 633 and 111. So I decided to search this 633. This forum and some other F150 forums had some interesting information on the 633 code but the only solution I was able to find was the fellow eventually replaced the PCM which solved the issue. Does anyone have any further information on this code? Due to work I have not gotten underneath to look at the connectors for the Tcase, it is manual by the way. I am wondering what will happen if I can find this connector and unplug it and go for a drive. The only other thing I have is the PCM and taking a look inside. This has really been a trip and I am tired of shifting this transmission on my own. I checked the fluid and the level looks good and the fluid is great with no metal particles or burnt smell.
Miesk had an article linked to a thread but I couldn't find his test information as he stated. So I hope someone has some more information. Thank you for your time.

 

Code 633 is definitely 4x4 switch closed. 111 is system pass.
On an electric shift 4x4, the wiring harness for the t/case comes from the shift computer behind the passenger kick panel, across under the carpet and drops through a hole in the floor of the cab down to the back of the transfer case where the plug is. So fairly easy to have a look at from underneath. Or unplug it at the shift computer (module).
I do know that there's a program inside the speedo that takes info from the vss, the RABS module and the cruise control and sends a signal to the PCM to help it decide when to shift. I've never heard of the 4x4 being tied into this system but I suppose it's not impossible.
There's also a program in the PCM that locks and unlocks the torque convertor and actually has slippage programmed in, which is a thought, but usually t/c problems cause a shudder when they're acting up.
Another thing to consider is maybe going back and testing those new parts, especially the TPS. New just doesn't mean what it used to.
One more fuel pressure test is to crimp off the return line and see what happens. That rise in pressure with the pump shut down is something I've heard of before and it seems to me it turned out to be regulator related.
Also, if the vss was covered in metal, it'll get covered again if there's bits in the fluid. Only way to do a good fix on that is to pull the cover, clean up everything you can and install fresh fluid. PITA, messy, but not an expensive thing.
That's all I can think of - you must be getting a little frustrated.

 

A little frustrated is putting it simply. It is my only means of transportation and I am getting tired and nervous also having to shift an automatic manually. I will take a look back at the TPS and the VSS. The MLPS is a ford part but I went with oriellys for the TPS so I don't remember the company on that. I just cant understand why that 633 is the only code. I hope to look at the connector, see what is going on and then try running the test with it actually in 4L just to see what happens. I have not taken a look at the RABS module. I will have to research that more. Cruise control works just fine as I use it all the time on the highway. I just reprogrammed the PSOM for my 33''s using the article that is floating around here and it is dead on with the radar trailers along the road but it did nothing for the shifting. You said something about the shift computer that I have not heard of before so that is worth a look also. Is the shift computer solely for electronic shift on the fly 4wd system? If so then I would think that I don't have that because I have the manual IE manual locking hubs and manual shifter down on the floor. But the other thread that spoke about the 633 code was saying that it sends a signal to the PCM to alter shift patterns when the truck is in 4wd and I think he had a manual also. Don't know how accurate that is. I think I found that thread here searching just 633.
At this point I am so frustrated I don't know what to do. I have gone over these sensors and searched online and I am at the point now of wondering if it is the shift solenoids or the pcm. But I cant get around the fact that no codes are present. Only the 633 which is why I am chasing this one now.
How can you tell when your T/C locks up? I am not too familiar with automatics and have read many threads about getting a higher stall speed and this and that but I am not sure what exactly they are talking about or why.
I don't know but I do not have the time or money to just surrender and take it to a shop who will tell me some crazy story of needing a complete rebuild. I dread repair shops. So thank you very much for the help. you have been the main person to keep coming back to this thread. I appreciate it.

 

I can sort of feel my convertor lock up when I'm on the highway; tap the brake pedal and it unlocks, you can watch the revs jump.
That TPS is worth a look for sure. I know all the guys I talk with that have been around these trucks for a while say "motorcraft only" for the TPS, PCV valve and VSS. Too many stories about people having issues with aftermarket stuff for those 3.
633 shouldn't apply to a manual shift (there's no shift module anyway) - the only thing that could refer to would be the little switch to light the 4x4 and low range bulbs on your dash - I think. Unless it also sends a signal to the speedo or PCM. I don't know about that; but if it does then that code could be related to your problem. 2 things I'd be checking out first anyway.

 

Thanks for the reply. I will check out the tps and that 4x4 switch. On top of that I need to troubleshoot the driver door lock that keeps working when it wants and install new radius arm pivot bushings.
Happy New Year.

 

This weekend i was able to spend some time doing some more troubleshooting.
I tested the TPS. It was within spec that the ford manual called for and it had a nice track to it as you rotated the throttle body, no skipping nice and smooth.
I pulled the VSS. There was some metallic "dust" if you will on it so I wiped it off and put it back in. Cleared codes by disconnecting the battery. Went for a drive no change.
So I concentrated on the 633 some more. Looking at the diagram in the ford manual for a manual shift transfer case, it would appear that the pcm gets input when the switch closes for 4 lo or 4 hi. This makes sense to me because I have this code saying the PCM thinks that 4 lo is engaged. So I wonder if this adjust the shift schedule. The manual was vague about it but lead to it in a round about way for troubleshooting the transmission. But it does not clarify if this shift scheduling is for the manual shift transfer case or electronic.
In any case, I disconnected the connector to the shift indicator switch, cleared codes and went for a drive. No change. However with the switch still disconnected I checked for codes and still received a 633. The computer for some reason still thinks that it is in 4 lo.
So the only thing I can come to is to pull the PCM and look it over and then check the inside of the transmission pan to make sure the correct filter is in. A friend of mine did the change out and flush for me a year back since he worked at jiffy lube at the time. I dont remember what type of filter is in there because looking at the ford manual there are two different types based on 2wd or 4wd.
Beyond that it looks like a visit to a shop may be in order because I have no idea. The only codes I get is a 633 everytime. Nothing else.
Can anyone shed some light please?

 

I wonder if you could have a short further up the 4x4 indicator wire (Lt Blue, black stripe) that is causing a reading that the 4low switch is activated when it's not.
I saw on one diagram where that wire goes to the cluster wiring (still lt blue/black) so maybe something in the cluster even ?
Something there is causing the 633.
Not that there's any guarantee that clearing that code will solve the problem, but maybe.
Like Edison said "I haven't failed - I'm finding lots of ways that don't work".

 

OK newish owner of an 88 f150 XLT 4x4 5.0 AOD. My truck runs great when fully warmed but when cold will stall from idle after a quick acceleration to move up a cars length then a drop throttle, like when moving up at a left turn lane. It will also do this occasionally when fully warmed but much worse when cold.
Gassy smell until warmed up.
Mileage around town 12-13 MPG
Mileage on engine unknown, junkyard 5.0 installed in 97.
Where is this MAP sensor and could that be the problem?

 

Been a while. I have still been chasing this issue. It actually is getting worse due to having to shift it myself that when i go to park occasionally it is actually in reverse. I have had a couple of close calls with this issue. I pulled the PSOM and that looks ok, nothing burnt looking. The only thing i can not get around is the code 633 4x4 switch. I plan on testing this out with the meter this weekend and pulling the computer to check that out. This is the only code i have.
Does anyone have a better wire diagram than the f150 manual online has of how the switch integrates to the system? I see how it only gives the indication light for a manual transfer case which i have. But the light works just fine and is never on unless i shift to 4wd. So if i am in 2wd why would that code be active? i am not really good with electricity so i am having to learn this as i go. The only thing else i can think of is to retest all the different sensors that feed into shift scheduling and/or throw parts at it.
Otherwise i am at a loss.
Also how do you align the MLPS without the alignment tool? I think that would solve the whole reverse oops thing. The MLPS is a brand new ford item also.
THanks for reading.