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i30 N i30N is not overboosting

So... bad news. Overboost is not working again... Today I went with some friends to do a B road blast. At the start the overboost was working good, but then we stopped for a few minutes and when I started the car again, overboost wasn't working.

Fun fact: After lunch I have done~200km (with overboost not working), then I stopped to cleaned the car, and oh surprise, overboost was back. I have done 60km more, stopped to put some gas, and again it wasn't working.

I don't quite understand why it is failing, either a sensor is failing or the ECU is defective... I'll have to go back to the dealer again.
 
So... bad news. Overboost is not working again... Today I went with some friends to do a B road blast. At the start the overboost was working good, but then we stopped for a few minutes and when I started the car again, overboost wasn't working.

Fun fact: After lunch I have done~200km (with overboost not working), then I stopped to cleaned the car, and oh surprise, overboost was back. I have done 60km more, stopped to put some gas, and again it wasn't working.

I don't quite understand why it is failing, either a sensor is failing or the ECU is defective... I'll have to go back to the dealer again.
Heatsoak into the intercooler I reckon, what ambient temperatures were there at the time?
 
Heatsoak into the intercooler I reckon, what ambient temperatures were there at the time?

I don't think so... 18-25°C outside and oil temp never above 115°C. All other I30N on the group were working good.

I mean it is not a bad theory (you ment that because the water from cleaning the car cooled down the engine bay right?). But in this case, tomorrow it should be working again, and I don't think it will. The first time that failed never worked again until reset.
 
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I don't think so... 18-25°C outside and oil temp never above 115°C. All other I30N on the group were working good.

I mean it is not a bad theory (you ment that because the water from cleaning the car cooled down the engine bay right?). But in this case, tomorrow it should be working again, and I don't think it will. The first time that failed never worked again until reset.
Try it and let us know what you find.
 
Sorry! I completely forgot to update this thread!

After a few months I filled with 98 octane instead of 95 and now the overboost is back! I wasn't thinking about it anymore.. it was like "oh the overboost is back again".

So now I only use 98 and everything is running perfectly!

Maybe the 95 was bad fuel or have water mixture on it and wasn't reaching real 95 octanes.. I don't know..
Both fuels are from Repsol

Hello Milho,

After you filled the tank with 98, did you put again 95? If anser is yes do you have the overboost light again?
 
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Update: Overboost has magically came back. However, I changed the petrol that I normally used to one that it is supposed to be "premium". Bad luck is that it came back when I was going back to the dealer but for the moment looks like it is working as it should...
 
I too am suffering the lack of overboost symbol on the dash so ran a test…

No overboost indication - 95RON
Disconnected battery for 1hour - overboost indication reappeared
Filled twice with 99RON - overboost indication remains
Refilled with 95RON indication since disappeared.

Im wondering if the recent change to E10 is a factor? I too am only getting about 3/4 boost on gauge…
 
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I too am suffering the lack of overboost symbol on the dash so ran a test…

No overboost indication - 95RON
Disconnected battery for 1hour - overboost indication reappeared
Filled twice with 99RON - overboost indication remains
Refilled with 95RON indication since disappeared.

Im wondering if the recent change to E10 is a factor? I too am only getting about 3/4 boost on gauge…

For me it has nothing to do with 95 because I always use this type of fuel and sometimes it works and sometimes it doesn't. However since the last ECU reset (it failed again but didn't add any post) I am starting to think of a new situation which can be the reason for the failure. Do you change drive modes often?

Regarding the boost gauge, can you specify what turbo you have (B1, C0 or D0, you can have a look at the plate on the right side of the turbo) and do a video? When I don't have the icon, I still have full boost.
 
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For me it has nothing to do with 95 because I always use this type of fuel and sometimes it works and sometimes it doesn't. However since the last ECU reset (it failed again but didn't add any post) I am starting to think of a new situation which can be the reason for the failure. Do you change drive modes often?

Regarding the boost gauge, can you specify what turbo you have (B1, C0 or D0, you can have a look at the plate on the right side of the turbo) and do a video? When I don't have the icon, I still have full boost.
Clutching at straws here as this post is over 5 years old but.... .did you ever get to the bottom of this problem? My turbo is only reaching 15psi and the green overboost light never shows, all this since its major manufacturer service too!