Limp mode at 5k rpm’s- need help

[TheBaseStinger]

Hey everyone,

Need help, no one can figure this out and I’m about ready to dump my car.

Problem
Car runs fine up until about 5k rpm’s. As soon as I hit anywhere near that or over the car goes into limp mode. Turbo psi reduces to about 1 psi. If I shut the car off and turn it back on it runs fine again. The code I’m getting is P0049 turbine spinning too fast.

When it started
I was driving to work one day and boom the car suddenly went into limp mode getting off the freeway. Had not made any changes in months. I literally don’t know what happened or what was different. Caught me off guard.

What mods were on the car with the car when it happened?
Car: 2019 Kia Stinger 2.0 Base

- Jun BL GT Catback exhaust
- Maintec High flow Catalytic Converter (Down pipe)
- Maintec Intercooler
- HKS Spark Plugs
- HKS BOV
- Burger Motorsports JB4
- Injen Intake
- PedalBox
- W1 Catch Can
- N75 BOV solenoid
- shark racing oil cooler

After the problem occurrence. What was done?
1). I removed the JB4 and the problem persisted. Same code
2). Removed the JB4 and put OEM catalytic converter back on. Same code
3). Bought a lap3 ECU tune and swapped it with my OEM tune (disconnected battery). Tune is running meth injection. Same code
4). Tried to adjust the wastegate. Problem got worse, bought a new waste gate, replaced the waste gate. Same code
5). Bought a new MAP sensor and installed it with battery disconnected. Same code
6). Checked for boost leaks, no leaks.
7). Swapped my boost sensor. Same code
8). Reverted BOV solenoid back to OEM solenoid. Same code.
9). Ran logs and sent them to David at Lap3. He said my car is not overboosting, my car is only hitting about 20 psi and something goes wrong but not sure what, thinks it’s the wastegate.
I had a similar problem back in august last year, limping at 5k rpm. I was able to fix it with a new high pressure fuel pump, turned out there was a recall on those. Got a new one from the dealer. Everyone is telling me it’s not my fuel pump. Ran my intercooler for almost a year with no problems.

What haven’t I done, but plan on doing.
- reconnecting the JB4 and running map 0 to send the logs to Terry.
- reinstalling my intercooler
- possibly buying a new turbo
- possibly buying a new fuel pump
S.O.S - Please help
If anyone out there has had an issue similar to this, limping at 5k rpm’s. I would appreciate you sharing what you did to fix this. I need your wisdom, thoughts and guidance. I can’t just throw more money at it blindly, I need a plan of attack.

 

[turboAWD]

Does the turbo have a sensor to detect turbine speed? Is the sensor maybe clogged / damaged? Or wiring?

I don't know if all turbos these days have such a sensor - I know the Q50 Red Sport does (it's the main difference between the regular Q50 and Red Sport engine, IIRC), which lets it spin faster / boost higher.

If it's saying your turbo is spinning too fast, it must be getting some signal to base that off of?

 

[Corleone1]

Does the turbo have a sensor to detect turbine speed? Is the sensor maybe clogged / damaged? Or wiring?

I don't know if all turbos these days have such a sensor - I know the Q50 Red Sport does (it's the main difference between the regular Q50 and Red Sport engine, IIRC), which lets it spin faster / boost higher.

If it's saying your turbo is spinning too fast, it must be getting some signal to base that off of?

No, Turbo dont have turbine speed detector. Its calculated by an algoritm. If one turbo overspeed the other turbos wg can be open and then the other tries to compensate and sets P0049 code. Mostly boost then also increase by rpm and then ECU shuts down. There is common problems with turbos EWGs, some have had the plastic broke, some have just stopped and then left wg stucked, can be full open, no boost until higher rpm or overshoot if its not will open... or in between. Seems mostly be right side. Also if the wg valve in hotside will go sluggish it could kill the EWG motor.

I have also been thinking of the ECUs amplifiers that runs the EWGs, if EWGs will be stucked, much current will go to the EWGs and maybe ECUs amplifiers will broke. EWGs should be calibrated to 1,3 V and 85%, probably means that the 1,3 voltage is there the mechanical stop is and should be. The 85% probably is that wg valve is 100-85% = 15% open when calibrated, this to have less overshoot and a smother boost buildup in a stock car.

I have asked several pros of the ECU and all said that the stock tune is the same in all, just different depending of the climate car is selling in and if it has E-gear and ISG.

Some also describe that bigger downpipes and racecats can be a reason for overboost, I havnt seen that myself. I also noticed if you run more than E30-40 and up, ECU can cuts of, probably depending of HPFP crash, if so, try to go back to lower E and see.