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2000 Kia Sephia - Transmission works, and then it doesn't

18K views 33 replies 5 participants last post by  Loyale 2.7 Turbo 
#1 · (Edited)
Hello everyone! I have a brain teaser that has me scratching.

I have owned my Kia for about 2 years. Replaced water pump and all the belts when we first bought it. Replaced the tires, plugs, and wires about 6 months ago.

About a month ago it starts having issues shifting. Bullet points for easy reading:
  • handles 1st and 2nd usually fine
  • When it acts up, As it starts to shift to 3rd it will drop into neutral, the engine will rev, I let off the gas. Then it will either go into 3rd or stay in 2nd.
  • If it stays in 2nd, every time you press the gas more than a small amount it drops to neutral and revs again.
  • If it goes into 3rd, everything is fine until the next time I stop and it moves to 1st/2nd.
  • I can pull the battery after it acts up, and it will work again, but with diminishing returns. First it resolved for a couple of days, then a day, now its minutes before it does it again.
  • Sometimes shifting to neutral while in motion, turning the car off and back on, then shifting back resolves it, but not always.
  • It does work fine from time to time with no issues.
  • Hooked it to code reader, and get P0733/P0734
  • When acting up, Check engine light is on and O/D Off Flashes. When fine, both are off.
  • When acting up it shifts into 1st very hard, shaking the car and almost killing the engine
  • All fluid levels are good
  • Speedometer and tach are working fine

This car is mostly an around town car, but it is also our long trip car. When working, we can take this on the road (and have) at 80 for 2+ hours and it runs fine. Get off an exit to get gas, and it starts acting up at the first red light. Reset it and drive another 2+ hours just fine. It does seem to "happen more" when around town then on the road.

Considering it runs fine "when it wants to" i don't believe the trans is shot, but i am not a mechanic and any mechanic I talk to wants to jump to trans first thing. I have tried to read up on everything on the board I can and every time i think i found the solution, the poster in that thread has an issue i didn't, like the speedometer not working, or it never resolving itself.

Any help is much appreciated.
 
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#2 ·
Started reading through this post. I overlooked it because his first issue wasn't mine. Later on it gets more similar.

http://www.kia-forums.com/2g-1998-2001-sephia/76263-2000-sephia-blinkin-o-d-light.html

Pulled the turbine speed sensor. Cleaned it. Noticed the gold "sensor" on the tip has a "shaved incline" on one side. The one picture in the thread is a side angle, but from what i can tell it is flat all the way around.

When i put it back in and took it down the road, it acted differently. At first it stalled out a couple of times,then went fine. Then acted up on the way back. When it did, it didnt feel like it was going into neutral, it was more like it was shifting to 3rd then to 2nd when i pressed the gas because i did eventually get tug on it. Let off and it would shift to 3rd.

SO probably the sensor?
 
#4 · (Edited)
Greetings,

Yes, if the behavior changed after removing/cleaning the sensor, then I would also conclude the sensor is related to the issue..

If you haven't already, would recommend signing up at kiatechinfo.com (see my sig.) - it's free, and you can view the service info. for your Sephia..

In the meantime, I've attached a (PDF) printout of the P0733 diagnostic tree for the Sephia - pretty well matches the steps jeszek took to solve his issue (flushing/cleaning trans, new VSS, new turbine sensor..)

Hope the info helps,
GottaCruise
 

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#3 ·
You mention that all fluid levels are good.... But you didn't say "if" you have changed the transmission fluid... JesZek is a good guy and has spent hours helping others..I'd believe and follow his advice..
Transmission fluid gets ignored right up to the time of transmission failure...KIA says to drain and refill the transmission EVERY 50k miles... The fluid MUST be compatable with (meets/excedes) DIAMOND III type fluid...any other fluid will damage the tranny... Valvoline MaxLife ATF is what we here have found to work without any problems...
Dave
 
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#5 ·
Thank you both for your input and support. :)

I have not flushed or changed the tran fluid, so I will do that tonight. Recomend seafoam the same as JesZek did or just new fluid?

Also does anyone know the part number or a special name for the turbine sensor? Cannot seem to find it anywhere online.
 
#6 ·
Greetings,

Always best to confirm locally, w/ part in hand if possible..

TRANSMISSION CASE & MAIN CONTROL SYSTEM (4AT2WD). Fits: Kia | Kia Parts Overstock

Item #44 - GENERATOR ASSEMBLY - PULSE
(4AT2WD). $35.01 MFW0121550A

--
I would follow JesZek's advise and run some Trans-Tune through before dropping the transmission pan and cleaning - that product will help loosen up any trapped "muck" in the valve assembly..

Getting the pan and filters clean -is key- to clearing out any trapped junk with the new fluid,

I would hold off on putting in any additives immediately after the cleaning / fluid change - run the vehicle 200-500 miles first to clear out any residual particles in the valve body..

--
If any doubt, you may want to consider finding a shop with the proper equipment to perform a (true) transmission system flush - e.g. a trans flush machine that will circulate trans cleaner through the (entire) system..

But if you have the time/resources/skill to perform the pan drop & clean / filter cleaning yourself, I would try this yourself as a first step - a proper trans system flush is expensive, and you would know the system is at least clean on the bottom end before having the service performed..

Hope the info helps,
GottaCruise
 
#8 · (Edited)
So I am back with good and bad news.

I bought Seafoam TransTune Thursday, put it in and could quickly feel improvement. Not much, but just a little. I took the car on a trip (had no choice) 200 miles round trip.

I noticed quickly that the problems had stabalized to a "predictable" set.
  • In 1st and 2nd gear, fine.
  • In 3rd and 4th gear, fine.
  • Getting from 2nd to 3rd, impossible.
  • Driving about 40mph in 2nd gear, move to neutral, turn it off, back on, into drive and were in 3rd gear and still doing 35.
  • Coming back down to 2nd and 1st after being in 3rd/4th it starts jittering and stuttering like it is waiting too long to shift back, almost kills the engine
  • 1 out of 6ish times starting it back it will not turn over. Play with the gears and let it roll, it will eventually let it start.

So.... with the advice of everyone, I did a fluid, filter, and seal change Sunday. Used valvoline maxlife as recomended. Once I was done, shifting became AMAZINGLY smooth. Still was seeing the issues listed above, but shifting gears was just sooo smooth. 1st and 2nd still jittered.

I ordered a transmission speed sensor. Received it today, installed, and believe it or not, the shifting was even better. The jitters at 1st and 2nd are gone so far, but still will not shift into 3rd/4th.

With all this said, i do not have an issue with my gauges, so could it be the VSS? I was under the impression the VSS makes the gauges mess up but i have had 0 issues with that. This is (I believe) the only thing i have left to do from the post by JesZek. Any thoughts before i replace the VSS?



TL;DR - Issues continue, but same issues every time. Transtune helped some, Fluid change helped a lot, TSS change helped even more, but still having issues.
 
#9 ·
Give it a little more time...If the valve body was really plugged bad it may take some time for the new fluid to work it's way through it... You also might want to run some more transtune through it after driving it a while... And like JesZek said you might want to drop the transmission pan and clean out the gunk...
It took a wile to get this way so it will probably take a while to get things moving properly again...
Dave
 
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#10 ·
Thanks for the quick response. I forgot to mention, I did drop the pan and clean it thoroughly. I did not have as much gunk in mine, but it was rather nasty and had a very dark look to it, almost that of motor oil. I will drive it tomorrow and see if that helps. So no changing the VSS right now in your opinion?

I will also say, i took it back out a bit ago and the jitters have returned, albeit much smoother.
 
#12 ·
It sure could be the speed sensor and/or the wiring harness connections going to the transmission... I'm working with another guy with a newer Spectra and he has found some bad (corroded) connections in the transmission wiring harness giving him intermittent tranny codes also..
There are so many variables.. I'm discounting clutches and bands because you say it sometimes works correctly. I'd give it time and drive it VERY gently and don't force shifts...you could damage the clutches and bands while the fluids get moving again.
Dave
 
#15 · (Edited)
Update on my pitiful little Kia.

I added the lucas as prescribed by Dr. JesZeK. Right out of the gate I saw improvements. It usually would act up when it was cold. Once warmed up I could pull over, turn it off and back on, and it would run perfect. This went for the first 50ish miles. After that we were back to acting up.

I've been watching my speedometer/tach closer. My speedometer is staying on track. Here is a new symptom: When stuck in 2nd gear, doing 40MPH as a benchmark, sometimes it will be doing 2k RPM, 3kRPM, 4kRPM. And i believe the tach is right as well as the motor will roaring at 4k, humming at 2k. In fact yesterday at one point i was doing 55MPH in 2nd, at 3kRPM which i thought was impossible.

When i pull over and put it in park and turn it off and back on, it will not start, will not even turn over. This has happened before but it used to be 1 in 6 and trying again it would work. Now it is more like 9/10 times, and it takes close to 10 minutes for it to resolve. Try to start and all you get is a single click.

One other thing, at various times the OD off button will not work. You can press it all day and it will not take you out of OD and the light does not come on.

At this point I am taking it in to the shop as it seems to be above my head. On the needle bearings, i believe he was referring to a set of bearings in the transmission, not the instruments. I think that was more of a "Get me off the phone" guess, but this shop is known in my area for being the best at finding the solution and not charging people for ridiculous things they don't need. I will update when I find something out to give this closure.

If anyone has a wild guess, im listening. I am leaning more toward a clutch issue of some sort now.
 
#16 · (Edited)
... I added the lucas as prescribed by Dr. JesZeK. Right out of the gate I saw improvements. It usually would act up when it was cold. Once warmed up I could pull over, turn it off and back on, and it would run perfect. ...
That is the expected results of the Seafoam Flush plus pouring Fresh Fluid and Adding the Lucas ATF additive.


... This went for the first 50ish miles. After that we were back to acting up. ... If anyone has a wild guess, im listening...
How long ago did you Unplugged the Battery terminals for enough time to reset the Computers?

Somehow I Believe that the Automatic Transmission's computer is acting and sounds to me that a Bad Grounding could also affect the Engine Start altogether...

Kind Regards.
 
#17 ·
How long ago did you Unplugged the Battery terminals for enough time to reset the Computers?

Somehow I Believe that the Automatic Transmission's computer is acting and sounds to me that a Bad Grounding could also affect the Engine Start altogether...

Kind Regards.
I have been removing the negative only, as indicated somewhere in this forum (possibly your thread). I have removed it as little as a few seconds, and as much as a few hours. So is the thought that the Trans Computer is bad, or that there is a faulty ground on the TCM? Would you recomend a replace before taking to the garage?
 
#18 · (Edited)
I am trying to do my Best effort to Help you fix that, but you shall understand that is not easy to Diagnose a car without seeing it "in Person" so use this advice at your own risk.

By the Sympthoms you've described, I believe that the problem is due to something electrical related, not mechanical, but that is my own opinion.

So, I Kindly suggest you to check the wirings, starting from the Ground wire at the Battery to the Body. Then Check the Automatic Trans Computer wirings, and the ECU Wirings.

In my Wife's "KiaStein" I made an "Extra" Ground directly from the Battery to the Engine, without removing the Original Wiring (Parallel). Mainly because I consider "Weak" the original design that sends the Ground directly to the Body and then the engine picks it from the Body, in the other side, you know: with age the metallic body will not transfer the electricity like when it was New... too many joints, dirt, rust... etc...

My wife's "KiaStein" also suffered from a Delay in Starting, but in my case, I found a GPS + GSM Vehicle Tracking and Disabling device, Hiding behind the instrument Cluster; it "waited" for GSM signal, prior to let you start the Car ... it was there for the Previous owner who purchased that car on a loan...

I Removed such device, bypassed the spliced wires and problem solved.

However I doubt it could be the same case, because you hear a "Click" each time you turn the Key while we didn't hear anything, we only had a delay...

So, I believe that some sort of False Contact 'could' be the Culprit on both issues, your Starting issue and the Automatic Transmission going Crazy, after it was working fine... Why?

Because if the Automatic transmission had something wrong, mechanically talking, it would Not feel nor drive "Good" sometimes, and it does "heal" for moments; also the Starter Works after many Tries.

I know there's a chance that it could be the Starter itself, but if it is going bad, it should Start "Slowly" the engine, like if the Battery is Weak, despite that it is in good Charge.

Could you Tell how does the Starter spins the Engine? ...

Anemic or Happy starting?

If it feels "Anemic" despite the Battery is Good, then you could consider the Starter itself to be serviced.

But if your Starter spins "Happy" when it engages, and your transmission works fine sometimes; I bet that there "Could" be an electrical issue somewhere... But as I wrote above, I can not be 100% sure without seeing your car and diagnose it in person...

So, my Advice is: Double Check for electrical wiring looseness, false contact and / or Bad Groundings, clean each terminal and plug, using electrical contact cleaner... Also remember that Aftermarket Fusibles usually fits loose and could cause electrical problems...

To do this is Cheap and worth try, If it doesn't work, take it to the Shop...

Good Luck,
Kind Regards.
 
#19 ·
I am trying to do my Best effort to Help you fix that, but you shall understand that is not easy to Diagnose a car without seeing it "in Person" so use this advice at your own risk.
I understand, and I want you to know that I am VERY appreciative of your help. I know it is difficult doing this over the web, and I keep coming back because you (and others here) are familiar with this vehicle more than I am. I do not take your help for granted and I understand that whatever is communicated to me may or may not help. Grain of salt with all. :D

By the Sympthoms you've described, I believe that the problem is due to something electrical related, not mechanical, but that is my own opinion.
I fully agree. I ended up taking the car on into the shop as he "had a few minutes". So he kept the car for a day, and called me to say he believes it is the clutch pack. Bascially he wants to do a rebuild. Keep in mind, I explained everything to him as I have explained here when I dropped it off. I asked how things "worked great" sometimes and not others. His response was "oh, i didnt know that. Im not sure now". Needless to say, i went and got the car. I will note it ran PERFECT on the way to the shop.

So, I Kindly suggest you to check the wirings, starting from the Ground wire at the Battery to the Body. Then Check the Automatic Trans Computer wirings, and the ECU Wirings.
And this is my next stop. This weekend I will go through all the wiring. I rechecked the codes being reported from the computer. Previously I had P0733/P0734 for 3rd and 4th gear ratios.

The codes I have today have changed. Today I have P0734 still, but P0733 is gone. I also have P0753 P0758 P0763 P0743, which are selenoid a,b,c electrical issue, and torque converter electrical issue (from what i read, correct if i am wrong).

This all brings it back to an electrical issue, unless all those items really have failed.

One other item: Could it be the transmission computer? I am still convinced it is electric, but the TCM is electrical also, so could it be the TCM causing all of this? I ask this because the OD button not working sometimes could also be electrical, but could be driven by the TCM.

In my Wife's "KiaStein" I made an "Extra" Ground directly from the Battery to the Engine, without removing the Original Wiring (Parallel). Mainly because I consider "Weak" the original design that sends the Ground directly to the Body and then the engine picks it from the Body, in the other side, you know: with age the metallic body will not transfer the electricity like when it was New... too many joints, dirt, rust... etc...
I will do this. Easy item and nothing to lose right? :)

My wife's "KiaStein" also suffered from a Delay in Starting, but in my case, I found a GPS + GSM Vehicle Tracking and Disabling device, Hiding behind the instrument Cluster; it "waited" for GSM signal, prior to let you start the Car ... it was there for the Previous owner who purchased that car on a loan...

I Removed such device, bypassed the spliced wires and problem solved.

However I doubt it could be the same case, because you hear a "Click" each time you turn the Key while we didn't hear anything, we only had a delay...
No, no device like that.

So, I believe that some sort of False Contact 'could' be the Culprit on both issues, your Starting issue and the Automatic Transmission going Crazy, after it was working fine... Why?

Because if the Automatic transmission had something wrong, mechanically talking, it would Not feel nor drive "Good" sometimes, and it does "heal" for moments; also the Starter Works after many Tries.
I am so glad someone else gets that. This is exactly my take. How can it work and then not if it is mechanical. Very odd situation.

I know there's a chance that it could be the Starter itself, but if it is going bad, it should Start "Slowly" the engine, like if the Battery is Weak, despite that it is in good Charge.

Could you Tell how does the Starter spins the Engine? ...

Anemic or Happy starting?

If it feels "Anemic" despite the Battery is Good, then you could consider the Starter itself to be serviced.

But if your Starter spins "Happy" when it engages, and your transmission works fine sometimes; I bet that there "Could" be an electrical issue somewhere... But as I wrote above, I can not be 100% sure without seeing your car and diagnose it in person...
I don't think it is the starter. I won't say it is "happy" but WHEN it works, it doesn't seem like it is going. Again, its working, and then its not. Typically it happens when the transmission is having issues. I had the issue this morning and decided to try a battery disconnect for 1 minutes (reset) and it worked. Cant confirm yet that that fixes it every time, but it did that time.

So, my Advice is: Double Check for electrical wiring looseness, false contact and / or Bad Groundings, clean each terminal and plug, using electrical contact cleaner... Also remember that Aftermarket Fusibles usually fits loose and could cause electrical problems...

To do this is Cheap and worth try, If it doesn't work, take it to the Shop...

Good Luck,
Kind Regards.
And this is my next step. Again, THANK YOU for all your help and support. I understand I have been a bit long winded and maybe even a pain in the tail sometimes, but I am very appreciative of all the help. If you were here, I would take you for a drink!

I hope to report back soon with good news. Fingers crossed!
 
#20 ·
I go along with Jes...
I believe it's an electrical problem and probably under the hood where corrosion from the environment causes problems... Earlier KIAs DID have corrosion and wiring problems that have been drastically reduced since Hyundai bought controlling shares In KIA.
The problems you are having come and go and a bad transmission will have problems 24/7...Bad bands and clutches only GET WORSE...never better..The fluid pulsing through the lines within your transmission CAN ad Do cause problems BUT the sticking valves and blocked pathways will improve from the things you have been doing...

I would look at any and ALL connections that have anything to do with the control of your tranny...

If it were my car I would be slicing open the harnesses and looking at each wire and connection after inspecting every plug and socket on it.... Black electrician's tape is CHEAP at Harbor Freight and your wiring probably could use a little "updating" of insulation anyway.. BUT that's me...

I really hope you can come back here with "I FIXED IT"...We here (for the most part) want you to enjoy your successes and your "ride"...
Dave
 
#24 ·
Hello all. Hope your Kia's are treating you well. Sorry to bring back an old thread but wanted to update everyone.

So we had a nasty winter, no garage, busy work and home, and pure frustration and laziness that prevented me from doing much with my kia over the winter. Recently i started over. To date i have replaced sensors, replaced trans fluid and filter, i ordered a tcu, cleaned and checked wiring multiple times. Nothing worked.

Last week i was working on a flashlight that was lightly working. I found the ground used the chassis to convey current. Later on i had an epiphany and remembered what loyal had mentioned about his kiastein... He ran a new ground from the trans to the battery because of weak chassis ground. I thought i had tried this but as i went through my mental notes i only recall verifying it was connected. I figured it was worth a shot at this point. I pulled the bolt holding the trans ground to the chassis and reconnected it to the same bolt on the chassis that the battery hooks onto... And tada! Working again. I am blown away at how simple that was and how silly i was for overlooking it.

Big shout out to everyone and a big thank you for helping me on this almost year long ordeal.
 
#25 ·
Awesome!

... Later on i had an epiphany and remembered what loyal had mentioned about his kiastein ... He ran a new ground from the trans to the battery because of weak chassis ground. ... I pulled the bolt holding the trans ground to the chassis and reconnected it to the same bolt on the chassis that the battery hooks onto... And tada! Working again. I am blown away at how simple that was and how silly i was for overlooking it. ...

I Told ya!:


... Somehow I Believe that the Automatic Transmission's computer is acting and sounds to me that a Bad Grounding ...

... a big thank you for helping me on this almost year long ordeal.
You're Welcome! :)

I'm really Glad that my Ideas helped again!

Thank you so Much for updating this thread with the solution. :thumbsup:

Kind Regards.
 
#26 ·
smitimus...
THANK YOU...for giving us FEEDBACK!!!
I'm sure you're gonna help others with Sephia transmission problems.
Between you and JesZek you have given others hope for their older KIAs...

Thinking about the 3rd gear problem(s) you have had and the ground from the transmission case and ground....The 3rd gear shift solenoid needs a good ground (as well as the other shift solenoids). Looks like 3rd requires a "better" ground to work properly..
Aluminum corrodes (white powder) and that is NOT a good conductor of electricity (read that as high resistance)... High resistance LIMITS the amount of current that can flow threw the solenoids and they would not pull in all the way...It all makes sense now...
Hope you stay and help others!
Dave
 
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#27 ·
I know this is old but I just started having this problem with daughter's car 98 Sephia, I was just going to change fluid and add Lucas, in search of best fluid for this car came across this site and praying this works. been looking for answers everywhere, i was thinking electrical too, but so many possibilities, I had already drained fluid and dropped pan, checked connections, now I will add ground hope this works, Thanks for all the info.....Let U know tomorrow
 
#28 ·
Welcome!

... I will add ground hope this works, Thanks for all the info.....Let U know tomorrow
Please, let us know the Results.

Kind Regards.
 
#30 ·
I should have mentioned this all started 2 days after one of the rubber lines split spraying fluid everywhere, I replaced the line and used de-greaser and hosed off the fluid that was on everything, it shifted ok the next 2 days then my daughter called saying wasn't shifting into third and od light flashing.
 
#31 ·
This issues Really needs further diagnosis.

I kindly suggest you to hook an OBD II Scanner and share here with us, the Codes retrieved, either new or stored.

Also, check if the Speedometer's needle is working properly, same with Tachometer's needle, if it has it.

Kind Regards.
 
#33 · (Edited)


OBD II Fault Code: P0734
Fault Code Definition: Gear 4 Incorrect Ratio
What does this Mean?

The purpose of the automatic transmission is to match the engine's optimum power and torque characteristics to the driver's desired rate of acceleration and speed by auto-selecting different gear ratios or 'speeds' to power the wheels.

When the code P0734 is set in the Automatic Transmission's Computer known as TCU, it means that it is seeing faster RPM's than specified, due to a difference between the rotational speed of the Input RPM's Sensor and the Transmission Output RPM's Sensor, when the vehicle is in 4th gear. This can occur during shifting or when driving at steady speeds. It often implies that the transmission is slipping.

Symptoms:

► Check Engine Light will illuminate.
► Vehicle will not shift properly.
► Decrease in fuel economy.
► In unusual cases, there are no adverse conditions noticed by the driver.
► In some cases, there may be performance problems, such as dying when coming to a stop after driving on the freeway and / or misfire-like symptoms.


Common Problems That Trigger the P0734 Code:

► Defective 4th gear related shift solenoid
► Defective 4th gear related gear set or clutch pack
► Defective Engine Coolant Temperature Sensor
► Defective Valve Body
► Dirty transmission fluid that restricts the hydraulic passages

 
#34 ·
There could be a Bad speed sensor, the Turbine Speed Sensor or TSS is the one that is more likely to Fail; I kindly suggest you to read this thread here, because you'll find interesting information regarding the issue; Photos, etc...

~► http://www.kia-forums.com/2g-1998-2001-sephia/76263-2000-sephia-blinkin-o-d-light.html

A good Flush with Seafoam's "Transtune" detergent, and fresh ATF refill will also Help; but better get that information on that thread, whose link is above.

Kind Regards.
 
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