Slight jerk when shifting from Park to Drive, Park to Reverse

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markjc

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2000 Lincoln LS 3.9L V8.

I've noticed that my car has a small jerk from Park to Drive and park to reverse or drive to reverse.

I'm thinking low/dirty trans fluid, anybody else? Also since it's a 'Sealed' transmission does anyone know what would a transmission fluid service cost at the dealership?
 
No searching I assume...
You have the classic symptoms of the solenoid assembly starting to fail. It's too late for just a fluid exchange to fix this, but it is a very good idea to go ahead and do one. Dealer charge is less than $200, but you'll want to add the charge for replacing the solenoid pack to that (probably $500 more including the part).
 
Also, take a look at some of the threads I had made about my car I just bought couple months ago. It was well kept, so no hard fails, but once we got to the bottom of it it turned out to be weak springs in the valve body. Tranny guy still wasnt sure the solenoid was bad (I did replace), but when in that area, especially on our 15 year old cars, I advise just do it all.
 
Oops, I should also note this only happens when the car is cold. If I let it warm up for 10 Minutes or so it wont jerk anymore.
 
Still sounds like a solenoid valve starting to stick, or a valve/spring in the valve body. You can take a chance on it just being the fluid.
Rule of Thumb: You change the fluid before there are any symptoms. After symptoms, it is usually too late for it to just be the fluid.
 
joegr said:
Still sounds like a solenoid valve starting to stick, or a valve/spring in the valve body. You can take a chance on it just being the fluid.
Rule of Thumb: You change the fluid before there are any symptoms. After symptoms, it is usually too late for it to just be the fluid.
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You think it's drivable for awhile till I can get it into a trans shop? I gotta get my alternator put in and 02 sensors swapped
 
From what you describe, it's probably okay.
 
There's also the possibility of a PCM issue caused by weak coils. The fluid change is going to be the cheapest/easiest thing to try first, the PCM will be second easiest. I changed my solenoid based on advice from this board, did not fix the problem. Sent the PCM based on later advice from here and it solved the problem. To be fair though, the PCM fix was relatively new at the time. I think mine was the second one here that the PCM fixed. http://siaelec.com/ If you have to go into the transmission it's a bear to get inside of. I'd address all possibilities outside the transmission before going inside of it.
 
Telco said:
There's also the possibility of a PCM issue caused by weak coils. The fluid change is going to be the cheapest/easiest thing to try first, the PCM will be second easiest. I changed my solenoid based on advice from this board, did not fix the problem. Sent the PCM based on later advice from here and it solved the problem. To be fair though, the PCM fix was relatively new at the time. I think mine was the second one here that the PCM fixed. http://siaelec.com/ If you have to go into the transmission it's a bear to get inside of. I'd address all possibilities outside the transmission before going inside of it.
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I did call the Ford dealership today for a diagnostic of the issue and they suggested there's a 'Computer' update for the car which could fix it. Is the PCM basically the same thing as the ECU? Because Ford calls the Alternator a Generator so I'm not really sure lol. The service advisor told me there's a service bulletin relating towards hard shifting and what not and a update of the 'computer' could fix the issue

Just wondering did anybody with hard/harsh shifting get their ECU/PCM or 'Computer' updated? and what were the before and after results

Edit; Other than that, Driving the car seems fine and it shifts smoothly
 
In this case, PCM and ECU are the same thing. However, be aware that the dealership and Telco are talking about two different things.

The dealership is talking about reprogramming the PCM to alter some of the parameters of how it operates. It may help, but if your car did not always do this, then it's not too likely to help.

Telco is talking about some hardware inside the PCM starting to fail. If that is the case, no amount of programming will help that. You have to remove the PCM and ship it to the company mentioned. They will test it and if they find that some of the FETs are failing, they will change those parts out. (I don't think that the dealers are much aware of this failure mode yet.)
 
joegr said:
... (I don't think that the dealers are much aware of this failure mode yet.)
Click to expand...

Hell, dealerships can't even troubleshoot the failing coil #4 causing EM interference to the PCM, throwing false Throttle Body codes. I mean they'll gladly put a brand new TB and position sensor on it for the tune of 2700$ and still have no resolution other then state on work orders that it may need a new PCM as the next attempt of a repair.


Recall the 1300$ 04 LSE I bought, had 2700$ worth of dealership TB work done to it and still puked on bad coils, specifically #4.

It still runs like an angry beast since I got my hands on it and changed all coils and plugs.

Dealerships can be good but they can be just as bad.
 
Yes, and now the LS is too old for even the good dealerships to know how to work on it anymore.
 
Best place to buy a complete set of LS repair manuals is probably from a dealership.
 
More 2 cents. All these guys really helped me through this as well, and the PCM came up on mine. I may still have to do that if any more issues pop, because what I read around that on the web it seems Lincoln used some low grade chips in it and if those are replaced (or as indicated repaired) alot of things shape up. Being an audio engineer this makes sense because heat sucks for electronics, especially from that time were they hadnt really beef up components to standards of today. Since my car was garage kept in California though and every part of the engine and interior is pristine, I kind of doubt my PCM is gone but still is going - but for how long who knows.

My symptoms were straight up HARSH versions of what you describe, with a varience of coming and going at times. The other factor is my shifts from 2 to 3 were harsh/delayed and the other shifts seemed less iffy but still not right. My car had 99k miles, I turned it 100k right after buying, and a receipt I have mentions harsh shifts at 90k. So with our age of car, my gut (im not pro like these guys) tells me you are in for some work in the control part of the tranny - either solenoid or valve body but again might as well do both if in there.

My car was perfectly driveable, but I was getting concerns that the harsh shifts would damage interior parts - and thats major 3k dollar rebuild. Thankfully, when the pan was dropped the findings were nice bright red tranny fluid and very little metal shavings on the magnet. Again supports my car was kept clean, just showing her age.

Good luck :)
 
joegr said:
In this case, PCM and ECU are the same thing. However, be aware that the dealership and Telco are talking about two different things.

The dealership is talking about reprogramming the PCM to alter some of the parameters of how it operates. It may help, but if your car did not always do this, then it's not too likely to help.

Telco is talking about some hardware inside the PCM starting to fail. If that is the case, no amount of programming will help that. You have to remove the PCM and ship it to the company mentioned. They will test it and if they find that some of the FETs are failing, they will change those parts out. (I don't think that the dealers are much aware of this failure mode yet.)
Click to expand...

First time concerning the PCM problem i have heard that the field effect transistors were the failing part.

are these jfet style or mosfets.

with the age of the LS could be either.but i would suspect jfet .

if they are the common TO92 / to220 /to247 packages they would be easy for anybody to replace.

if they were smt would be a bit harder but with air easily doable.

anybody got a schem ? know where i can find one ?

tried google,no luck.
 
grizzlyls said:
More 2 cents. All these guys really helped me through this as well, and the PCM came up on mine. I may still have to do that if any more issues pop, because what I read around that on the web it seems Lincoln used some low grade chips in it and if those are replaced (or as indicated repaired) alot of things shape up. Being an audio engineer this makes sense because heat sucks for electronics, especially from that time were they hadnt really beef up components to standards of today. Since my car was garage kept in California though and every part of the engine and interior is pristine, I kind of doubt my PCM is gone but still is going - but for how long who knows.

My symptoms were straight up HARSH versions of what you describe, with a varience of coming and going at times. The other factor is my shifts from 2 to 3 were harsh/delayed and the other shifts seemed less iffy but still not right. My car had 99k miles, I turned it 100k right after buying, and a receipt I have mentions harsh shifts at 90k. So with our age of car, my gut (im not pro like these guys) tells me you are in for some work in the control part of the tranny - either solenoid or valve body but again might as well do both if in there.

My car was perfectly driveable, but I was getting concerns that the harsh shifts would damage interior parts - and thats major 3k dollar rebuild. Thankfully, when the pan was dropped the findings were nice bright red tranny fluid and very little metal shavings on the magnet. Again supports my car was kept clean, just showing her age.

Good luck :)
Click to expand...

As an audio engineer ( you ) familiar with heat and transistors the only FET i could see would be affected by the heat would be a mosfet but they are generally used as an amp and i would think have a heat sink.

a signal jfet would be used for signals i would think and not get hot ?

i would think in this app it would be a jfet.

tho i have replaced many jfet's that have failed i dont think it was because of heat.

i wonder if some of these failures could be contributed to the old " cold solder joint " problem ??
 
I haven't cracked one of these open, and I don't have schematics to the internals. I can say that the FETs in question are driving the 12V solenoids in the transmission. I'm not sure what the maximum current is, but it is over one amp, so I wouldn't call it a "signal." The suspicion (not proven that I know of) is that high voltage transients such as those caused by marginal ignition coils is behind these failures. Certainly, that seems reasonable for the FETs that sometimes fail that drive the coils. It is a little more of a stretch to link this to the failing FETs for the transmission solenoids.
As the LSes continue to age, I would expect to see more electronics failures. At some point, electrolytic caps drying out will become a problem on many of the modules.
 
joegr said:
I haven't cracked one of these open, and I don't have schematics to the internals. I can say that the FETs in question are driving the 12V solenoids in the transmission. I'm not sure what the maximum current is, but it is over one amp, so I wouldn't call it a "signal." The suspicion (not proven that I know of) is that high voltage transients such as those caused by marginal ignition coils is behind these failures. Certainly, that seems reasonable for the FETs that sometimes fail that drive the coils. It is a little more of a stretch to link this to the failing FETs for the transmission solenoids.
As the LSes continue to age, I would expect to see more electronics failures. At some point, electrolytic caps drying out will become a problem on many of the modules.
Click to expand...

Yes,,a jfet wont handle a full amp of current.
mosfets cant handle spikes like the old bi-polar transistors could.
so it looks like a signal and power amp to the solenoids.
I looks like in that app the mosfets would need a "bias " circuit consisting of two resistors and a diode.
my first guess would be the diode not capable of handling the voltage spikes,,surviving but letting the mosfet be over powered and heating up to much and failing.
replacing the mosfet would be a quick fix until the next spike ..
the next step would be to incorporate a dropping resistor ,,common in small amps.

I haven't seen inside one of these but you think they use a standard cap and not an smt type ?

them oil caps if underrated in a power supply will fail over time.

i pick up lot's of tv's and fix them for less than $5 because of bad cap's.

just google bad cap's .
 
I tried to go back and find the vid about the pcm repair, but dont remember where it was. Anyhoo, you can be right about cold solder joint, but this was specifically referencing a handful of motorola chips to replace. I bet thats what SAI does right off the top, plus any other cleanup. Joe is also right, and reminds me of the time when I took in my 40 Mitsubishi tube tv in due to the picture half disappearing. Fortunately for me, service was just replacing all the old caps and such about 100 bucks and it was like brand new again!
 
roncoinc said:
...I haven't seen inside one of these but you think they use a standard cap and not an smt type ?
...
Click to expand...

I don't think that's the right question. Electrolytics come in thru-hole and SMT, as due tantalums. I assume that they have a mix of both electrolytic and tantalum. I know that the Town Car and Mark guys are having issues with electrolytic caps. I mostly use tantalums for bulk caps in my designs because of the age problem. Still, for the really big ones, the cost is just too high. On the other hand, the cost of ceramics in the 10 to 47uF range has gotten low enough to start using those where I would have put tantalums (usually because I already have a few in the switching power supplies anyway). It's easier to justify if it reduces the unique part count on the BOM.
 
joegr said:
I don't think that's the right question. Electrolytics come in thru-hole and SMT, as due tantalums. I assume that they have a mix of both electrolytic and tantalum. I know that the Town Car and Mark guys are having issues with electrolytic caps. I mostly use tantalums for bulk caps in my designs because of the age problem. Still, for the really big ones, the cost is just too high. On the other hand, the cost of ceramics in the 10 to 47uF range has gotten low enough to start using those where I would have put tantalums (usually because I already have a few in the switching power supplies anyway). It's easier to justify if it reduces the unique part count on the BOM.
Click to expand...

I dont consider an smt an electrolytic,,it is not physically the same..never seen an smt wound with oil.
tants are regularly replaced with can's in old designs when they fail as a better option.

in low power a tant will suffice but you will find in most any PS's can's are used because of durability.
tho i must admit in most boards due to cost or by design they are underpowerd on purpose.

ceramics have their place but cant filter and hold a charge like a can.

the cost of any cap is now so cheap when replacing there is no reason not to go a bit more heavy duty.

typical TV PS cap,,16v,250uf ?? 25 cents for a 24v 450uf.
sure,,load up time may take take a couple milliseconds more but the end user wont notice .

reading your reply again,,why would you replace a tant with a ceramic ??
they do diff job ?

replace a tant with a can ok,,but not a ceramic.

" ceramics in the 10 to 47uF " ,, what voltage range you talking ??

and how would they....,,,
LOL !!!

Joe,,i wonder how many are reading saying WTH they talking about !!!

I think we should get back to what TR is failing and it's rating and what supports it.

it well could be one of the support components that is allowing the TR to fail ?? you think ?
 
I promise you that SMT electrolytics are electrolytics just the same.
Ceramics are needed for very low ESR for high speed circuits. I do digital design mostly. The voltage range I am in is mostly below 5V, usually 3.3V or 1.8V. Of course, I do some 12V stuff too.
Oh and $0.25 is often too high for a cap. (10 caps a board, 100K boards a year and it adds up, if you can do it with $0.05 caps instead)
 
joegr said:
I promise you that SMT electrolytics are electrolytics just the same.
Ceramics are needed for very low ESR for high speed circuits. I do digital design mostly. The voltage range I am in is mostly below 5V, usually 3.3V or 1.8V. Of course, I do some 12V stuff too.
Oh and $0.25 is often too high for a cap. (10 caps a board, 100K boards a year and it adds up, if you can do it with $0.05 caps instead)
Click to expand...

I understand the cost consideration with volume.

Do you have any more info on the failing FET ?
what was the source of that info ?
 
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