C63 not getting full boost
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GLC63 S Mbux facelift
Who disconnected it in the first place?
Solid 10+ years on my 205 C63 here.This doesn't "just happen" on a completely untouched car.
You've either got a hidden limp mode (check the engine data screen for HP limiting, common even with zero codes), exhaust flaps playing up (huge one on these, triggers soft limp), or something's been touched:
Xentry datalog boost requested vs actual will tell the story quick. What year/mileage and any mods at all?
Classic 205 boost thread.
C63 owners come on....
Solid 10+ years on my 205 C63 here.This doesn't "just happen" on a completely untouched car.
You've either got a hidden limp mode (check the engine data screen for HP limiting, common even with zero codes), exhaust flaps playing up (huge one on these, triggers soft limp), or something's been touched:
- Recirc pipes/valves messed with
- Cheap intake/downpipes
- Exhaust flap mod or muffler delete
- No CPC tune if it's a FL and you've done any hardware
Xentry datalog boost requested vs actual will tell the story quick. What year/mileage and any mods at all?
Classic 205 boost thread.
Tuned by a cery reputable company in the UK
im assuming when j had the coolant thermostat done last year they didnt fit it correctly and the pipes come loose over time.
I scanned the car and it also came up with code P226D 07 which relates to the petrol particle filter missing
Bizarre scenario as I never had a check engine light regarding this code .... sent all info to the people that tuned i they said it could be possible that a software update/ stock flash was done by Mercedes before I purchased the car when a independent dealer took it to Mercedes for an oil change before they sold it to me.
All in all its got a engine oil service next week then it goes down 90 miles trip to the tuning company so they can look at it and do their wizardry
Wish me luck
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AMG C63s Coupe
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its a stage 2 tuned car
Tuned by a cery reputable company in the UK
im assuming when j had the coolant thermostat done last year they didnt fit it correctly and the pipes come loose over time.
I scanned the car and it also came up with code P226D 07 which relates to the petrol particle filter missing
Bizarre scenario as I never had a check engine light regarding this code .... sent all info to the people that tuned i they said it could be possible that a software update/ stock flash was done by Mercedes before I purchased the car when a independent dealer took it to Mercedes for an oil change before they sold it to me.
All in all its got a engine oil service next week then it goes down 90 miles trip to the tuning company so they can look at it and do their wizardry
Wish me luck
Tuned by a cery reputable company in the UK
im assuming when j had the coolant thermostat done last year they didnt fit it correctly and the pipes come loose over time.
I scanned the car and it also came up with code P226D 07 which relates to the petrol particle filter missing
Bizarre scenario as I never had a check engine light regarding this code .... sent all info to the people that tuned i they said it could be possible that a software update/ stock flash was done by Mercedes before I purchased the car when a independent dealer took it to Mercedes for an oil change before they sold it to me.
All in all its got a engine oil service next week then it goes down 90 miles trip to the tuning company so they can look at it and do their wizardry
Wish me luck
Stage 2 tuned by a “reputable” UK company + P226D 07 (GPF/particle filter code) + recirculation pipes that magically came loose after the thermostat job last year = exactly the pattern I was talking about.
That code doesn’t just appear for no reason it means the ECU knows the particulate filter is gone or bypassed. Your tuner should have handled that properly in the map (along with CPC on a FL car). The loose pipes are just the final straw.
Send it back to them and get them to do a proper Xentry datalog (boost requested vs actual under load) while they’re “doing their wizardry” 9 times out of 10 it’s a software/hardware mismatch on these Stage 2 setups.
Good luck with the trip Darky these 205s bite you in the **** when the tune isn’t 100% dialled in...
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⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
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GLC63 S Mbux facelift
Fair enough mate, now we’re getting somewhere 😂
Stage 2 tuned by a “reputable” UK company + P226D 07 (GPF/particle filter code) + recirculation pipes that magically came loose after the thermostat job last year = exactly the pattern I was talking about.
That code doesn’t just appear for no reason it means the ECU knows the particulate filter is gone or bypassed. Your tuner should have handled that properly in the map (along with CPC on a FL car). The loose pipes are just the final straw.
Send it back to them and get them to do a proper Xentry datalog (boost requested vs actual under load) while they’re “doing their wizardry” 9 times out of 10 it’s a software/hardware mismatch on these Stage 2 setups.
Good luck with the trip Darky these 205s bite you in the **** when the tune isn’t 100% dialled in...
Stage 2 tuned by a “reputable” UK company + P226D 07 (GPF/particle filter code) + recirculation pipes that magically came loose after the thermostat job last year = exactly the pattern I was talking about.
That code doesn’t just appear for no reason it means the ECU knows the particulate filter is gone or bypassed. Your tuner should have handled that properly in the map (along with CPC on a FL car). The loose pipes are just the final straw.
Send it back to them and get them to do a proper Xentry datalog (boost requested vs actual under load) while they’re “doing their wizardry” 9 times out of 10 it’s a software/hardware mismatch on these Stage 2 setups.
Good luck with the trip Darky these 205s bite you in the **** when the tune isn’t 100% dialled in...
2024 october a sales dealerships took it to mercedes for a oil change (I believe they must have done a software/ecu update)
I purchased in november 2024
The coolant thermostat was done by a independant garage near me not the tuning company so as far as im aware the tuning company did the job correct but its going back to them next week for them to look at
The max boost issue they seem to think and I quote
That i will have to look at could be it has downpipes but stock software so waste gate duty will be at a high % as the turbos are expecting back pressure that isn't there anymore
To note : my car is GLC63 s 2020 model
Thanks for the prompt replies mate I really appreciate will keep this thread updated
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AMG C63s Coupe
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2019 C63CS
I think he was asking what CPC means.
Computer Powertrain Control. Tuning it removes factory set torque, speed and acceleration limits. Something I think most people who tune the engine overlook. The rest of the car such as the transmission are not expecting the higher torque of a tuned engine, so removing the factory set limits will bring the drivetrain in line with the higher engine outputs.
Having issues like this in a tuned car is definitely another story. Goes to show that letting people know that the car is tuned is important when posting issues.
Computer Powertrain Control. Tuning it removes factory set torque, speed and acceleration limits. Something I think most people who tune the engine overlook. The rest of the car such as the transmission are not expecting the higher torque of a tuned engine, so removing the factory set limits will bring the drivetrain in line with the higher engine outputs.
Having issues like this in a tuned car is definitely another story. Goes to show that letting people know that the car is tuned is important when posting issues.
Last edited by superswiss; May 6, 2026 at 03:57 PM.
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From: Keep it simple - keep it OEM
AMG C63s Coupe
@superswiss
Okay i remember. Talked with high level tuning guy.
He told if you chip tuning engine module C63 you have to buy a new CPC too. He told me you can not or not fully? overwrite it. Before i never heard about it. Normaly you do new set up in engine module - thats all.
Okay i remember. Talked with high level tuning guy.
He told if you chip tuning engine module C63 you have to buy a new CPC too. He told me you can not or not fully? overwrite it. Before i never heard about it. Normaly you do new set up in engine module - thats all.
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c450
Ah Superswiss your right, my apologies to Jack. Also on a side note, my friend had the wires that go to the bov eaten by rats, and it would still go to full boost in the gauge, but you could feel the car having issues with boost and you could hear it.
Last edited by mokawop; May 6, 2026 at 04:08 PM. Reason: update
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⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
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GLC63 S Mbux facelift
Its in For oil change and smoke test today only from a local indy, let's see if they find any boost leaks
Then a 2 hour drive Saturday morning to the tuner buddy
