Kia Soul Forums :: Kia Soul Owners banner

Acceleration and Power Problems

25K views 15 replies 11 participants last post by  stephanie.aguirre77  
#1 ·
My 2015 KIA Soul, 2.0l, has started intermittently losing power when attempting to speed up at highway speeds and when accelerating from a dead stop. Forums are full of this problem and suggestions to replace the catalytic converter or clean/replace the throttle body. My son had the same problems with his 2012 KIA Soul and had numerous things replaced (two throttle bodies, the catalytic converter, the control module, plus more) and the problem still persists. I have yet to see anyone say doing any of those things actually fixed their problems. Anyone?
 
#3 ·
Of course I'm not wanting to go down that path. In my son's case a KIA dealer couldn't find a reason and a supposedly reliable shop kept "diagnosing" different problems (to their credit, they quit charging him after the first couple of failures and then gave up). The question remains: has anyone actually found the root cause of this very common problem with KIA Souls? I've not seen a single success story.
 
#4 ·
That is no where near enough information to diagnose the car or even take a stab it. Sounds like you need to find a good mechanic, they are unfortunately few and far between. As for this being a common problem I would say it is not as I haven't come across and intermittent one like that on here. Catalytic converter issues are not that common, it is a small percentage that has them and most of those cars have poor maintenance or lots of history of cold start misfires that was never addressed and destroyed the cat over time. Converters also don't cause intermittent problems, it is either a problem or not but it doesn't go away. Crank position sensors cause such issues but usually get progressively worse and cause stalling not just an intermittent power problem. What codes have these guys that worked on it been getting if any? What exactly are the symptoms and how often, after driving how long, any other issues, how bad is the acceleration?
 
#5 ·
No codes at all. Yesterday tried to accelerate at 70 mph to pass. Car slowed drastically instead of accelerating. Check engine light flashed a few times then quit. Let up on accelerator, then pressed again and things returned to normal. Once off the highway, speeding up from a dead stop and car bogged down, then slowly sped up. This happened a couple of times. Nothing on dash. I have a basic diagnostic unit and it shows no codes. Today wife was driving and tried to speed up on the interstate using cruise control and the car did the same thing (don't know about check engine light). I drove it around town today and just a little weird shifting. Still no codes. That's all I got. Have an appointment with a shop next Thursday.
 
#6 ·
The only time the engine light will flash like that is for a misfire so you most likely have a bad spark plug or coil. My wife's Soul would bog like that here and there so I popped the plugs put and on one of them I saw a little carbon trace on the porcelain. Replaced it and that's all it was, cheap fix. If you tell a mechanic that the light flashed when it happened they will know what to check.
 
#7 ·
100% in the 2012 and probably the 2015 simply the crankshaft position sensor. I had to find the issue as Kia had my car a week and had no clue. I researched for days and finally someone mentioned a si.ilar probkem! Many others have found this on this site or I suggested it and that WAS the issue. It's an inexpensive fix! Wish they would do a recall as its not just the 2012 (which was my year!).
 
#8 ·
My 2015 KIA Soul, 2.0l, has started intermittently losing power when attempting to speed up at highway speeds and when accelerating from a dead stop. Forums are full of this problem and suggestions to replace the catalytic converter or clean/replace the throttle body. My son had the same problems with his 2012 KIA Soul and had numerous things replaced (two throttle bodies, the catalytic converter, the control module, plus more) and the problem still persists. I have yet to see anyone say doing any of those things actually fixed their problems. Anyone?
I’m not certain if you’ve tried replacing Oxygen Sensor.
A faulty sensor should show in a diagnostic.
 
#10 ·
I found the cause.
VVT SOLENOID

Low oil level/psi the lack of oil and heat dryes the oil on the vvt solenoids witch effects the variable timing

Their was no engine cide showing or visabke with code reader.

Remove it clean it use a 9v battery to engage the vvt if it moves clean it put oil on it re-install

If cleaning it dose not make it work replace them their are 2

This fixed the stalling at 4k rpm
 
#12 ·
My wife's 2020 soul 2.0 was having misfire issues. I pulled the fuel rail and found some water in with the gas. I drained and wiped the fuel tank. Now after it sits for maybe 30 minutes, I crank it and it idles smooth. I go into drive and mash the pedal, it struggles and dies. I stop and crank it again and it will do it a second time. after starting it a third time, it runs and drives smooth. It only happens on a cold start. I'm wondering if the fuel pump is losing it's prime.
 
This post has been deleted
This post has been deleted