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2025 audi s4 with hp tuners

Practical Reflash Tuning

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Discussion and questions related to the course Practical Reflash Tuning

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Hello everyone i am.hoping someone here may be able to help or give some insight on a issue ive ran into. On a 2015 audi s4 8.5 running hp tuners.

The problem that we are having is no matter what we do we are not able to increase boost pressure from the supercharger hp tuners does not seem to be holding the bypass valve shut to allow boost to increase. Hp tuners sent update with pid settings for the bypass valve to no avail. We tried adjusting the torque demand settings that hp tuners allows user to change and nothing changes when it is driven. Car makes stock boost levels just fine as soon as you try to get more it almost hits a wall and just dumps the rest of boost on us. Hp tuners has been tryi g to help sort this issue out and as of now we have made no progress.

Are we missing something or is there a setting hp tuners needs to allow us to change to get more power and boost. Before hp tuners was setup the car was running apr stage 1 tune this allows13 psi boost without pulley change. We are trying to replicate results that the apr tune gave without as much knock retard as the apr had.

Fuel pressure remains stable. Lambda is slightly lean for direct injection but i cannot see this being the issue as it wont make even 1 psi more boost.

The last update hp tuners sent was a complete fail and had to go back to the other map we had due to the new map from hp tuners not communicating with the tcm.

Are we missing something here or is hp tuners not quite ready to ru the 2015 audi s4?

If anyone can help it would be greatly appriciated.

The car does have a tcm tune done aswell previously by apr i believe.

Another issue we are having is reading the map off the stock ecu it does not seem to want to let us download the map from ecu i suspect this is due to old locked apr map could the old apr tune have somesort of effect if the oe audi tune was not flashed on it first before the hp tune was loaded on?

It is kike the car hit a protection or limiter setting no matter what we do.

Thank you in advance for the help.

Unfortunately I haven't had the opportunity to look at any Audi/VW on the HP Tuners software. It is quite possible that HP Tuners still haven't got a fully developed definition for your ECU. With some ECUs it's not always possible to download the existing rom file out of the ECU, but rather the VCM Editor software will load a base ROM file that's suited to your ECU model/year and you can start from there. This 'should' be the stock file but of course you'll lose any modifications that have been performed.

At this stage you're probably best to continue working with HP Tuners on this as it's likely related to the mapping. I would suggest however that if you can over ride the valve and confirm you can physically raise the boost then this will prove you can get the boost you want, then this will prove the system isn't being mechanically limited.

Thank you for the responce we will keep working with hp tuners.

Hello Charris79.

I'm running into a similar issue with my 2013 S5. The bypass valve opens up around 5500 rpm and is dumping boost down to 12-15 psi. The car pulls with 18-21psi until 5500 rpm. I can't figure out why. Was wondering if you had any luck. Also I have been trying to tune a launch control. The car is standard, I can't get the engine to build any torque or boost at the 2 step. As well as if I turn traction control off, the stationary 2 step goes away and now it will rev all the way out at stationary.

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