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Hi, I have a 2002 zx2 with a 4 speed automatic, and one night after work I drove home and noticed my car held first gear until I hit 3500rpm, then it seems to go into third gear because it will sit 2000-2500rpm until I hit 45-50. If I exceed 50 it has reached as high as 4000rpm without shifting, and will just drop to idle(1000rpm) when I let off the gas.

After two weeks since the first problem I finally got the p0705 code, so I replaced the transmission range sensor(aka neutral safety switch) and for now my code is gone, but I still have the same problem. Yesterday when I started it there was a brief rattle as if it was rod nock, and it only sometimes happens. I’ve checked multiple connectors and the fluid is full(although it’s starting to look brownish) and I’ve added some Lucas stop slip to no avail.

Recently the car had a bad crank sensor(now replaced) and a bad voltage regulator/alternator(also replaced) it was a three month period between the last repair and the beginning of this problem.
 

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Today I had a problem with the car starting. At first it lit up like normal, then when I went to start it it was as if the battery was low. The dash lights went really dim, car didn’t even try to turn over, but I discovered the battery still read full voltage.
I tried to start the car in quick succession(as this worked in the past when the starter seized) and it seems that after doing it a bunch the lights on the dash stay on longer.

Still didn’t start...

so I disconnected the battery for about five minutes and reconnected it, and it seemed to start up like usual(not great, but no power loss)

I just figured I’d add this issue to see if the symptoms line up with a common problem, although I believe them to be two separate problems.
 

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My escorts are the 2nd gen LX kind, but the business of the trans using only 2 and 4th might be that it is working in the 'limp mode'. This can happen if the Vehicle Speed Sensor is not working, i.e. having a bad connector or a broken magnet inside, etc. The car will still run and drive, but without the working speed sensor it cant tell when to use the other gears. Staying in low till fairly high rpm could indicate the Vehicle Speed Sensor magnet is weak, and not putting out enough of a signal at low rpm. The magnet is deep inside the VSS - so replacing the VSS may help. I dont know of any way to test the thing.**

The business of the car staring slowly, as if the battery was discharged, I would guess is a bad battery connection at one of the terminals, or corrosion inside the battery cable that is hidden by the insulation. I have had a battery terminal that seemed tight, but the car failed to even crank over. Cleaning the battery post (made of lead) and the inside of the battery terminal was the solution. I did the cleaning by scraping lightly with the blade of a penknife. Lead corrodes slowly, but lead oxide is a lousy conductor or electricity. Also check that the ground cable is still firmly bolted to whatever it is connected to on your car. On mine, the ground cable connects to a bracket bolted to the transmission.

** And good luck on getting the VSS out. They are a common problem to extract, since they corrode in place, and the top of the VSS is only of plastic, and will break off if attacked with vise grips. I have had difficulty with each of my escorts in initially removing the VSS - even when the transmission was out of the car on my workbench!

If you do a search you should find lots of postings about VSS removal.
 

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My escorts are the 2nd gen LX kind, but the business of the trans using only 2 and 4th might be that it is working in the 'limp mode'. This can happen if the Vehicle Speed Sensor is not working, i.e. having a bad connector or a broken magnet inside, etc. The car will still run and drive, but without the working speed sensor it cant tell when to use the other gears. Staying in low till fairly high rpm could indicate the Vehicle Speed Sensor magnet is weak, and not putting out enough of a signal at low rpm. The magnet is deep inside the VSS - so replacing the VSS may help. I dont know of any way to test the thing.**

The business of the car staring slowly, as if the battery was discharged, I would guess is a bad battery connection at one of the terminals, or corrosion inside the battery cable that is hidden by the insulation. I have had a battery terminal that seemed tight, but the car failed to even crank over. Cleaning the battery post (made of lead) and the inside of the battery terminal was the solution. I did the cleaning by scraping lightly with the blade of a penknife. Lead corrodes slowly, but lead oxide is a lousy conductor or electricity. Also check that the ground cable is still firmly bolted to whatever it is connected to on your car. On mine, the ground cable connects to a bracket bolted to the transmission.

** And good luck on getting the VSS out. They are a common problem to extract, since they corrode in place, and the top of the VSS is only of plastic, and will break off if attacked with vise grips. I have had difficulty with each of my escorts in initially removing the VSS - even when the transmission was out of the car on my workbench!

If you do a search you should find lots of postings about VSS removal.
Thanks, as for the power issue it didn't seem to have problems this morning so hopefully that one is gone. I will work on getting the vss replaced in the next few weeks. the timing really sucks because I'm about to move, so I might not get to it right away.
 

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That I dont know; since I dont have a 3rd gen. On the 2nd gens the speedometer in the cluster is cable driven from the VSS - so if the cable gets pulled out of the VSS the speedo and odo stop moving. But the VSS also puts out a varying signal to the PCM to indicate the car speed from its internal spinning magnet - for shifting purposes.
 

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That I dont know; since I dont have a 3rd gen. On the 2nd gens the speedometer in the cluster is cable driven from the VSS - so if the cable gets pulled out of the VSS the speedo and odo stop moving. But the VSS also puts out a varying signal to the PCM to indicate the car speed from its internal spinning magnet - for shifting purposes.
So I'm guessing that means it can screw with the transmission without messing with my dash readings?
 

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Discussion Starter #9 (Edited)
Are you proactively checking for codes or waiting for a dash light and then checking for codes?
I recommend checking for codes (and pending codes) without waiting for a dash light and report back.

My 1995LX only used 1st and 3rd gears when I had a bad solenoid in the transmission:
https://www.feoa.net/threads/how-to-replace-1-2-shift-solenoid-on-atx-1991.82837/

How many miles are on the car?
I did check for codes last night with no luck. I also thought that a solenoid could have gone bad. I know very little about how transmissions operate, but from what I understand some "gears" in the car share a physical gear? That was based on planetary gears though and I've seen disassembled transmissions that don't have planetary gears so maybe I'm way off?
 

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Still ohm out the solenoids in the transmission and see if you can get them to click with voltage applied.
 

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update

I haven’t yet gotten to checking resistance or voltage tests, but today while driving to work I had my cel pop up. Just checked and I’ve got a p0340 (cam position sensor) which I replaced two years ago, but because of the recent voltage regulator issue I won’t dismiss the possibility that it’s gone bad. Not sure if it would affect the transmission, but I’ll stop by the auto parts store and see if I still have warranty on it.

I also have a p0171 (system too lean bank 1) so these might be a separate issue. I’ll update tomorrow wether or not a new sensor fixes them.
 

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Discussion Starter #14
Today I replaced the vss with no luck, however the little plastic. Can I test solenoids without removing the transmission pan?
 

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On the 2nd gen Escorts, the connector to the solenoids is on the lower front of the F4EAT; I guess it is in the same place on the 3rd gens. If you could work out the wiring (some diagrams are in the Electrical and Vacuum Troubleshooting Manual, EVTM), you could connect a voltage (of about 12 volts) to the proper wires; but I dont know if you would be able to hear the tiny soft click when a solenoid was energized. I doubt there would be any difference in the impedance of the solenoid while-energized-versus-not - but certainly you could tell if a solenoid was 'open', i.e. havinf a broken winding.
The auto trans in a 2nd gen has four solenoids; I dont know if the 3rd gen trans have a fifth one. Even with removing the pan, only two of the solenoids are accessible from the bottom. To get to the other two you have to drop the valve body. While this isnt rocket science, it involves some interaction with the shifting mechanism between the valve body and the manual shifting shaft. So its not just a simple push-it-back-up and insert the bolts. And the gasket between the valve body and the case can get cracked too. Its sort of a brittle gasket and real thin.

With the solenoids out of the trans and held in the hand, you can tell if they are 'switching' or not, by blowing into them. Even so, each solenoid has a tiny filter screen, which could be clogged; though with the several of these transmissions I have rebuilt, none of them had that problem and all worked just find.
 
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