2020 Kia Stinger GT Line Limp Mode

[marchoshd77]

I have a 2020 Kia Stinger that is jumping into limp mode and will not accelerate above 2500rpm. I have an OBDII reader and bought EOBD-Facile software for my Mac to read the diagnostic codes from the car. I get a P0299 underboost and a P0088 Fuel rail pressure too high. I figure the Fuel pressure code is there as the turbo isn't producing the boost needed to match the intended fuel pressure increase which is why its triggered.

Diagnostic checks:
1. All tubing from the turbo to the intercooler then the throttlebody are fine and tight.
2. The Turbo is spooling freely without damage or missing blades
3. The boost sensor is working and producing boost.
read 15psi from the sensor

Not sure what to check next after this.

 

[Kia Stinger]

I have a 2020 Kia Stinger that is jumping into limp mode and will not accelerate above 2500rpm. I have an OBDII reader and bought EOBD-Facile software for my Mac to read the diagnostic codes from the car. I get a P0299 underboost and a P0088 Fuel rail pressure too high. I figure the Fuel pressure code is there as the turbo isn't producing the boost needed to match the intended fuel pressure increase which is why its triggered.

Diagnostic checks:
1. All tubing from the turbo to the intercooler then the throttlebody are fine and tight.
2. The Turbo is spooling freely without damage or missing blades
3. The boost sensor is working and producing boost.
read 15psi from the sensor

Not sure what to check next after this.

Welcome. This topic has been moved out of the community lounge and into the main Stinger forum.

 

[marchoshd77]

Adding to the troubleshooting steps. I checked the waste gate and its reading 4.06V and it seems to be moving so I don't believe that is the issue.

When I slowly accelerate the engine it clips around 2500rpm but it doesn't seem that its limp mode or semi-limp mode since it will sometimes let the RPMs go to 3k or 3.2k but then cuts back down to 2500. Acts like a miss but the OBDII tool doesn't seem to catch that.

 

[Deviate]

Adding to the troubleshooting steps. I checked the waste gate and its reading 4.06V and it seems to be moving so I don't believe that is the issue.

When I slowly accelerate the engine it clips around 2500rpm but it doesn't seem that its limp mode or semi-limp mode since it will sometimes let the RPMs go to 3k or 3.2k but then cuts back down to 2500. Acts like a miss but the OBDII tool doesn't seem to catch that.

Does it reset itself after being off for a while? Could be the map sensor or the hpfp. The hpfp will come and go at times and seem like limp mode. The map sensor will do similar. Mine would be fine until it got hot and them shit the bed. Just had it replaced under warranty, plus the cel that got thrown. Better example for what I experienced would be running down the hwy fine then out of nowhere nothing. No matter what the pedal input 2500 would seem to be max rpm. Car would slowly go but passing was not really an option. The other thing could be a bad injector

 

[marchoshd77]

Does it reset itself after being off for a while? Could be the map sensor or the hpfp. The hpfp will come and go at times and seem like limp mode. The map sensor will do similar. Mine would be fine until it got hot and them shit the bed. Just had it replaced under warranty, plus the cel that got thrown. Better example for what I experienced would be running down the hwy fine then out of nowhere nothing. No matter what the pedal input 2500 would seem to be max rpm. Car would slowly go but passing was not really an option. The other thing could be a bad injector

It happens when the car is cold or hot. Granted its 95 degrees here in FL so is it really cold? But I start up the car and drive it and as long as I don't go over 2500rpm it runs fine. going over that it acts like it goes into limp mode but there are no CELs to indicate the car is in that mode. Not sure how to check the hpfp assuming you mean (high pressure fuel pump)? I do get the P0088 Fuel pressure too high so I am having a hard time believing its an issue with the fuel pump. It might be something to check though.

 

[Deviate]

Adding to the troubleshooting steps. I checked the waste gate and its reading 4.06V and it seems to be moving so I don't believe that is the issue.

When I slowly accelerate the engine it clips around 2500rpm but it doesn't seem that its limp mode or semi-limp mode since it will sometimes let the RPMs go to 3k or 3.2k but then cuts back down to 2500. Acts like a miss but the OBDII tool doesn't seem to catch that.

Does it reset itself after being off for a while? Could be the map sensor or the hpfp. The hpfp will come and go at times and seem like limp mode. The map sensor will do similar. Mine would be fine until it got hot and them shit the bed. Just had it replaced under warranty, plus the cel that got thrown. Better example for what I experienced would be running down the hwy fine then out of nowhere nothing. No matter what the pedal input 2500 would seem to be max rpm. Car would slowly go but passing was not really an option. The other thing could be a bad injector

It happens when the car is cold or hot. Granted its 95 degrees here in FL so is it really cold? But I start up the car and drive it and as long as I don't go over 2500rpm it runs fine. going over that it acts like it goes into limp mode but there are no CELs to indicate the car is in that mode. Not sure how to check the hpfp assuming you mean (high pressure fuel pump)? I do get the P0088 Fuel pressure too high so I am having a hard time believing its an issue with the fuel pump. It might be something to check though.

First where are you in Fl.? And yea dumb hot here, im in Venice. Anyway ive had a few friends "lose" the fuel pump on their 2.0's so thats why i brought that up. My map sensor obviously like i mentioned.

Id say run it thru the dealer to diagnose it. Then go from there if you have warranty or have to do it on your own dime. Shouldn't be anything or very minimal to have kia tell you what it is. Instead of throwing parts at it

 

[marchoshd77]

Does it reset itself after being off for a while? Could be the map sensor or the hpfp. The hpfp will come and go at times and seem like limp mode. The map sensor will do similar. Mine would be fine until it got hot and them shit the bed. Just had it replaced under warranty, plus the cel that got thrown. Better example for what I experienced would be running down the hwy fine then out of nowhere nothing. No matter what the pedal input 2500 would seem to be max rpm. Car would slowly go but passing was not really an option. The other thing could be a bad injector

First where are you in Fl.? And yea dumb hot here, im in Venice. Anyway ive had a few friends "lose" the fuel pump on their 2.0's so thats why i brought that up. My map sensor obviously like i mentioned.

Id say run it thru the dealer to diagnose it. Then go from there if you have warranty or have to do it on your own dime. Shouldn't be anything or very minimal to have kia tell you what it is. Instead of throwing parts at it

I am in North East Orlando (Chuluota). Its possible that it could be either of those but since the pressure reading from the OBDII shows atmospheric pressure and when I gas it I get another 2psi it seems to be working. Also the P0088 code for high fuel pressure really goes in contrast to the fuel pump not providing enough fuel or pressure. I was hoping to get more information online but these kind of issues seem to be rare or the car is not old enough to have an abundant amount of Forums and Threads on the issue.

 

[Deviate]

I hope you get it figured out, sorry i couldn't help much

 

[marchoshd77]

I hope you get it figured out, sorry i couldn't help much

I appreciate the insight. If I figure it out I will post what I did so others can learn.

 

[marchoshd77]

I am using ODB-Facile software on my Mac with a Wifi ELM 327 adapter to read the computer. The data in the picture is me slowly accelerating the engine while the car is in park and when the car hits around 2500rpm it starts to essentially misfire. Now I am not sure if limp mode would purposely misfire the engine but I doubt it. I am starting to lean towards plugs and coil packs for the car. Thoughts?

 

[Deviate]

View attachment 81711
I am using ODB-Facile software on my Mac with a Wifi ELM 327 adapter to read the computer. The data in the picture is me slowly accelerating the engine while the car is in park and when the car hits around 2500rpm it starts to essentially misfire. Now I am not sure if limp mode would purposely misfire the engine but I doubt it. I am starting to lean towards plugs and coil packs for the car. Thoughts?

Have you pulled your engine cover off yet? If not check for rodent damage too. They like our wires.

As for thoughts on plugs and/or coils, thats a good thought. Plugs are easy enough to do, and relatively cheap enough to eliminate that possibility.

 

[Snicklefritz]

if that is a misfire it is a bad one to cut out at only 2,500 rpm. probably more than one plug and or coil pack.

 

[marchoshd77]

So I replaced the plugs and no dice. Ordered a set of coils to see if I can fix it with new coils on Sunday.

 

[Snicklefritz]

bad coils will ruin new plugs. it takes more than a couple of days, more like two weeks so hopefully you will be fine. my new plugs started misfiring after about two weeks on the bad coil pack.

 

[marchoshd77]

Replaced the coil packs this afternoon and I am still getting the same issue. Generated a report on output from the ODBII software. I see the car misfiring several times but I don't see what else could be the problem? I don't think its a fuel problem since I get a pressure too high from DTC. Wastegate works, all the hoses to the intercooler and to the throttle body are in good shape and the connections are tight. Ideas?

 

[Snicklefritz]

what about that rodent damage suggestion?

 

[G-507177]

what about that rodent damage suggestion?

Where would I see that? The wiring looks fine all around the engine compartment.

 

[Snicklefritz]

^^^check the seals around the hood too. Any chewed spots should be easy to see. I recall seeing pictures of soft material chewed by rats, so, anywhere 'chewable' material is used.

 

[Deviate]

Where would I see that? The wiring looks fine all around the engine compartment.

I know on mine they got under the engine cover. Pretty obvious to see there. But you just did plugs so you would have seen something.

Last thought, what about your injectiors? And id honestly check the map sensor again for good measure.

 

[marchoshd77]

I know on mine they got under the engine cover. Pretty obvious to see there. But you just did plugs so you would have seen something.

Last thought, what about your injectiors? And id honestly check the map sensor again for good measure.

When I was running the diagnostics I was getting atmospheric pressure readings from the computer and when I would accelerate the engine it would go up 2lbs during some boost so it appears to be working. Its getting beyond me with what is wrong with this car.