S3 feels a bit flat after service

[Damo S]

Since having a service my car feels a bit flat. It has stage 2 remap but to me it doesnt feel like Im getting that midrange torque shunt that it did before. No fault codes or misfires, and its still boosting to the same it did after the remap (22.5psi) according to torque pro.

They changed the spark plugs (same NGK racing plugs as previously fitted), oil, haldex pump replacement thats about it.

No fault codes or misfires according to torque pro.

It might be coincidence. It might be my expectations (being too use to it). It might also have something to do with the fuel having sat in the tank for nearly 6 weeks now.

Just after some ideas really. It could be the map sensor lying about the boost level, or perhaps it's pulling the timing (knock sensor detecting knock maybe due to fuel, or perhaps the sensor is on the way out).

 

[Phil-1]

Have they done a software update and wiped the Map?


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[Damo S]

I wondered that, but its boosting to 22.5psi in all gears and revs to 7krpm, neither of which it did before the remap.

 

[Damo S]

The car seems down on fuel as well, i.e. getting about 35mpgs on a trip where Id expect closer to 40 for the way the car was driven. The off boost response feels lacking to. I'm hoping it's just a tank of bad fuel which has resulted in the timing being pulled.

googling suggests that fuel in a tank will start to go off after a few weeks and it will kill the performance. Mines been in the tank for 6 weeks now and still a 3rd of a tank left. Hopefully that will explain it.

 

[AlS3BE]

Could it be your plugs? If the heat rating is too cold carbon build up could cause it not to fire properly. If it’s too hot the you get pinking. Either way the ecu will try and ******/advance timing to compensate which will result in flat spots.

 

[Damo S]

"They changed the spark plugs (same NGK racing plugs as previously fitted)"

But yes might be something to do with them, but not sure what they could have done. The plugs were identical. The ones which came out looked all clean too so no running issues with them previously.

 

[AlS3BE]

"They changed the spark plugs (same NGK racing plugs as previously fitted)"

But yes might be something to do with them, but not sure what they could have done. The plugs were identical. The ones which came out looked all clean too so no running issues with them previously.

Try filling up with some premium/super unleaded fuels and see what happens.
Only other thing I can think of is that variable timing gubbins, n95 valve or something like that.

 

[Damo S]

yeah. using up whats left and refilling with fresh fuel is the first step. I have a sneaky its something else though. Even before this I thought there were some days it felt brisker than others, so it could be something to do with the cam lifters etc. Just annoying there arent any fault codes.

 

[Damo S]

I do think the car felt a little better today from the outset. Did some timed tests on just the old fuel and actually the numbers were about right. I then put in a load of new fuel . After a bit of a run it felt perhaps a little smoother and had a touch more shunt in the midrange, but otherwise the numbers were comparable to previous tests.

So to conclude it's my butt dyno failing. Perhaps the warmer weather has played a bit of a part too, since it was going really well in the winter when it was very cold.