Thread: Td5 overboost issue

A couple of things to note....

Without comparing both ECU tunes with accompanying logs, it's almost impossible to ascertain exactly what is going on, although a faultcode can be pretty conclusive.

If the car originally came with an MSB ECU then it is an EU2 engine, this means that it will definitely not be a MAF related error... But only IF the NNN tune is also EU2.

If it's not then the "overboost" is probably the least of your worries.

Let's just say the correct tune has been provided by the tuner for that engine version, if it has then the only reasons for any kind of boost cut related issue will be to do with either:

1. Boost levels going beyond whatever the tuner has set.

2. Boost levels going beyond what your specific sensor can actually do.

3. Sensor incorrectly calibrated.

If it's MAF related, you've got the wrong tune installed.

If you post a log from a nanocom Evo, leave it in .csv format.

Yep, new data required, the sensors don't usually take too long when they start to fail.

That previous info relates to old type tuning, as I mentioned before, the MAF should be rescaled with new tuning to accept higher air flow though I only saw a max figure of 624 on the old log ( which, if you were running the MSB ECU at the time wouldn't have given you the symptoms as the MSB doesn't use the MAF in fuelling calcs)
However, the highest actual reading on the old type tuning on a NNN ECU was 675 before cut.

As an aside, I did note being on the verge of over boosting at the 74 second mark.

Of course once again, this all depends on

1: If the Tune file you have purchased is the modern tuning method
2: If yes then they should have rescaled the parameters ( usually around 800max for MAF and 1.6bar if using the stock MAP sensor ).

Probably all very confusing, in short, if you get new data and you observe the airflow on the Nanocom going from high 600's to zero while using the NNN ECU on full noise, that means A: that is the cause of your issue and B: The Tuner didn't rescale the MAF ( new method ) Ditto above 1.42 bar boost.

Tomorrow

Writing ( with interruptions of course ) while you posted James

Originally Posted by discorevy

Yep, new data required, the sensors don't usually take too long when they start to fail.

That previous info relates to old type tuning, as I mentioned before, the MAF should be rescaled with new tuning to accept higher air flow though I only saw a max figure of 624 on the old log ( which, if you were running the MSB ECU at the time wouldn't have given you the symptoms as the MSB doesn't use the MAF in fuelling calcs)
However, the highest actual reading on the old type tuning on a NNN ECU was 675 before cut.

As an aside, I did note being on the verge of over boosting at the 74 second mark.

Of course once again, this all depends on

1: If the Tune file you have purchased is the modern tuning method
2: If yes then they should have rescaled the parameters ( usually around 800max for MAF and 1.6bar if using the stock MAP sensor ).

Probably all very confusing, in short, if you get new data and you observe the airflow on the Nanocom going from high 600's to zero while using the NNN ECU on full noise, that means A: that is the cause of your issue and B: The Tuner didn't rescale the MAF ( new method ) Ditto above 1.42 bar boost.

Tomorrow

Confusing, yes. But get the gist of it. Fault code is 20,2 Overboosting.

STAGE1MSB.CSV
STAGE2NNN.CSV

Originally Posted by discopete

Confusing, yes. But get the gist of it. Fault code is 20,2 Overboosting.

STAGE1MSB.CSV
STAGE2NNN.CSV

I'm going to say MAP sensor related.
If there was no overboost faults when you first installed the tune, then try changing the sensor.
However, if it has faulted since installing, the tuner may not have calibrated the sensor correctly, or it's out of range as James has mentioned.

Send the log to Storm and ask them if they can fix it.

Edit, If you need to buy a new MAP sensor, especially if going to VGT, get this one and have it calibrated, they are a direct fit 4 bar sensor ( Shack can do it if storm can't )
Bosch 0281002316 Pressure / Temperature Sensor | Automotive Superstore

Originally Posted by discorevy

I'm going to say MAP sensor related.
If there was no overboost faults when you first installed the tune, then try changing the sensor.
However, if it has faulted since installing, the tuner may not have calibrated the sensor correctly, or it's out of range as James has mentioned.

Send the log to Storm and ask them if they can fix it.

Definitely faulted with new tune. I'll see what Storm have to say and provide any updates/resolutions.
Much appreciate the help you guys have provided.

Peter