[Griff500]

All, hoping you can help me with this please

My car doesn’t seem to be pulling as cleanly as it used to, I haven’t changed anything but the logs are showing something is amiss

A log from today
https://datazap.me/u/griff500/log-15...?log=0&data=22


A log from a year ago with an identical setup when the car was running great
https://datazap.me/u/griff500/log-14...ta=21&solo=3-5

I’m not hitting boost target and stft’s are very different from one bank to the other just in the range when the car feels a bit flat
WDGC is also around 5 higher than previously across the rev range

Does this look like a boost leak? Would this explain stft’s being off also?

Help appreciated

[RocketSurgeon]

You might have a clogged/melted cat. I saw similar symptoms and logs from another member a couple months back.
The cats really don't like the heat from higher power levels. If the cat gets all melted and clogged, that cylinder bank can't breathe as well, fuel trims go all weird, and the turbo doesn't spool as well.
Both turbos feed into the same intercooler, so all the cylinders get the same boost. You aren't too far off boost target, but the spool seems a little sluggish.
The other guy figured out that a compression tester can thread into the pre-cat O2 bung to test back pressure. The back pressure should not even be enough to register on the gauge. He was seeing 8 psi on the melted cat. You could also do a manual inspection, but that means dropping the downpipes.

[Griff500]

Thanks, that could be a good shout!

My downpipes are catless but this could be a secondary cat issue

I think I’ll try with the midpipes disconnected and see what happens

[Nexus313]

Let me know how it goes... I have similar issues and I'm pointing towards my primary and secondary cats

[Griff500]

Unfortunately no change with the midpipes disconnected (catless)

https://datazap.me/u/griff500/log-15...-25&zoom=0-106

Any other ideas?

[RocketSurgeon]

Have you tried clearing the lambda adaptations?

[Griff500]

Yeah I tried before and after resetting lambda adaptations, no changes in the logs

[RocketSurgeon]

I'd be looking at the injectors and the O2 sensors.
Are you running the downpipe fix?
What index are your injectors?
I always dismissed the idea of leaking injectors until I tested mine and found 2 GUSHING fuel, so they are problematic, especially the ones below index 12.
O2 sensors are good for about 100k, so if you're above that, they might not be reading correctly. They can drift out of range and give bad readings without throwing codes.