Neon transmission shifting problems w/ error codes

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Need help with weird transmission problem. It doesn't want to shift.

Ho All,

So yesterday on the way to work my neons automatic transmission decided to act up and start having shifting problems. It doesn't want to shift to 3rd or 4th. I was able to pull over turn the vehicle off and let it set for a minute. Rowing through the prndl selector causes a significant clunk from the transmission. I checked the level and it's full. It's bad enough that it tripped a check engine light. When I pulled the codes it displayed a few including
P0700, P0720, P0731, P0732, P1790, and P0715, all transmission related and none I've seen or dealt with as I've always had manual transmissions up until this point. I've been looking to replace the idle air control valve and shift solenoid while my parents are visiting as they're common failure spots with the neon. Like I mentioned it failed randomly. All help appreciated with this.
 
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Make sure under the radiator support the wiring harness is in tact and not damaged.

Also another common failure point on Neon's is the solenoid pack on top of the transmission, it is an easy job you just need to clean it thoroughly before removal. This is probably the most common failure point which is a lot of reasons why Neons were junked because mechanics claim the transmissions are bad which in reality it is just the solenoid pack.
 
Make sure under the radiator support the wiring harness is in tact and not damaged.

Also another common failure point on Neon's is the solenoid pack on top of the transmission, it is an easy job you just need to clean it thoroughly before removal. This is probably the most common failure point which is a lot of reasons why Neons were junked because mechanics claim the transmissions are bad which in reality it is just the solenoid pack.
Thanks. That's what I've read. When you say solenoid pack do you mean the shift solenoid.
 
Thanks. That's what I've read. When you say solenoid pack do you mean the shift solenoid.
They are referred to as both shift solenoid or solenoid pack, I personally just always refer to it as the solenoid pack.

Has the transmission been maintained? is the fluid burnt?, before dumping money into it I would drop the pan and inspect as well.

Do you have a good scan tool or did you do the key dance to get those codes?
 
They are referred to as both shift solenoid or solenoid pack, I personally just always refer to it as the solenoid pack.

Has the transmission been maintained? is the fluid burnt?, before dumping money into it I would drop the pan and inspect as well.

Do you have a good scan tool or did you do the key dance to get those codes?
This is what my scan tool found. The person I bought it from years ago hardly drove it and had it exclusively dealership maintained. I changed the fluid and filter when I bought it, then had it changed a couple of months ago. The fluid is still bright red and doesn't smell burnt. i know that for some reason shift solenoids and idle air control valves are a known failure spot on 2nd gen neons. I think this is why so many automatic ones end up in pull n pays. I've yet to see a manual one. Speaking of that how difficult is it to swap to a manual transmission?
 
They're all ratio errors, Input Speed Sensor error, And Output Speed Sensor error DTC's.

First do a good visual inspection of the wiring harness around the front & top of the transmission! Requires some disassembly of components on top of the trans to get a good look.

Does the Speedometer act up or drop out?
 
They're all ratio errors, Input Speed Sensor error, And Output Speed Sensor error DTC's.

First do a good visual inspection of the wiring harness around the front & top of the transmission! Requires some disassembly of components on top of the trans to get a good look.

Does the Speedometer act up or drop out?
No the speedometer doesn't act up. I was able a few times while driving to go from D to 3 then back to D and sometimes it wil upshift to 3rd then 4th. It helps to be at light throttle. It did upshift to third then slam back to 2nd then not go out of second After that.
 
Have you had the pan off for cleaning? Once the magnets load up they stop being effective (filtering).
 
Have you had the pan off for cleaning? Once the magnets load up they stop being effective (filtering).
If you have enough material on the magnet to the point that it is clogging up the filter enough to harm filtering then your transmission is toast to begin with.
 
If you have enough material on the magnet to the point that it is clogging up the filter enough to harm filtering then your transmission is toast to begin with.
It's got nothing to do with the full-flow filter, the magnets are the primary source for wear metal removal from the fluid. Most of the particles captured by the magnets will go right through the filter unless you have a bypass / kidney filter that is effective down to ~1 micron.

Have you ever seen "black" ATF? All that fluid has gone through the filter but much of that black can get pulled out by the magnets.

Magnets can actively filter 24hrs a day. Keep them clean. Keep them working.
 
Need help with weird transmission problem. It doesn't want to shift.

Ho All,

So yesterday on the way to work my neons automatic transmission decided to act up and start having shifting problems. It doesn't want to shift to 3rd or 4th. I was able to pull over turn the vehicle off and let it set for a minute. Rowing through the prndl selector causes a significant clunk from the transmission. I checked the level and it's full. It's bad enough that it tripped a check engine light. When I pulled the codes it displayed a few including
P0700, P0720, P0731, P0732, P1790, and P0715, all transmission related and none I've seen or dealt with as I've always had manual transmissions up until this point. I've been looking to replace the idle air control valve and shift solenoid while my parents are visiting as they're common failure spots with the neon. Like I mentioned it failed randomly. All help appreciated with this.
Please state year, engine size, 3 or 4 speed.
 
It's got nothing to do with the full-flow filter, the magnets are the primary source for wear metal removal from the fluid. Most of the particles captured by the magnets will go right through the filter unless you have a bypass / kidney filter that is effective down to ~1 micron.

Have you ever seen "black" ATF? All that fluid has gone through the filter but much of that black can get pulled out by the magnets.

Magnets can actively filter 24hrs a day. Keep them clean. Keep them working.
Black ATF is not metal that is clutch material, burnt fluid and oxidation.
 
Have you ever cleaned a transmission magnet before? What colour is that material?
Many times I work on them its often a dark silver metallic color, and once again black fluid is from burnt fluid, clutch material and oxidation.

I challenge you go find a transmission with burnt oxidized fluid that you claim to be metal and put your magnet to it to clean that fluid on video, lets see that fluid turn nice and red again.
 
Sounds like you've been keeping up on your maintenance. Have you ever had the pan off? You might find a clue as to what's happened.
No. I took it into the mechanic for an ignition issue and told them while they have it to go ahead and change the fluid and filter as it needed it. Since then it dail randomly on the way to work a couple of days ago. Neon forums point out that the shift solenoid is a common failure spot on this vehicle that causes similar symptoms.
 
Make sure under the radiator support the wiring harness is in tact and not damaged.

Also another common failure point on Neon's is the solenoid pack on top of the transmission, it is an easy job you just need to clean it thoroughly before removal. This is probably the most common failure point which is a lot of reasons why Neons were junked because mechanics claim the transmissions are bad which in reality it is just the solenoid pack.
Is the solenoid pack or shift solenoid a relatively easy diy? Are there any brands that you'd recommend? I don't want to fix this more than once.
 
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