2008 MS3 hesitation

[SP1988]

So the car is a 2008 Canadian model.

The problem it's having is it will hesitate going into boost, sometimes almost feels like a rev limiter, it will stay around 0-3psi for a bit before making full boost. It will mostly do it in 1st gear.
The car has a tune that runs about 20psi, it ran fine on that tune and mods, nothing changed.
Air fuels are in the mid 11s when it happens. Doubt it's a spark issue because it happens at lower load.
Everything I've checked was good.
Tried loading a stock tune, no change.

Any ideas? It must be somewhat common. How common are throttle body or waste gate actuator failures?

Here are the mods:
Cobb AP v2
Upgraded intercooler
Downpipe, high flow cat with catback
Aftermarket intercooler hoses
Aftermarket MAF housing
MAC boost solenoid
Aftermarket BOV
These are all the relevant mods that I know of.

Thanks

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[rigor]

watch your hpfp if it dips below 1000 under load your pump is giving you issues, happens around 2500-3000 rpm

mine was dipping to 600 so something to check

[SP1988]

Thanks, the car is low km and the AFRs looked good but I'll check it

[MSMS3]

If you are going WOT below 3,500-4,000, the turbo has to spool to build boost. With an aggressive tune, maybe your tune is soft at low rpm by design to try to control torque at lower rpm. It’s easy to create excessive torque at 20 psi at lower rpm under load. That bends connecting rods.

I would expect to see that softness when first coming on boost in the 3,000-3,500 rpm range in every gear, though, not just first.

Mazda even detunes the ECU for less max torque in 1st and 2nd in the OEM tune for this reason. Aftermarket tunes let you achieve full power, but often still soften it down low to protect the rods.

But, if this is something new and different with no change in hardware or tune, then, yes, look elsewhere.

[SP1988]

It's new and it still happens on the stock tune

[MSMS3]

Originally Posted by SP1988 It's new and it still happens on the stock tune

? ? ? What’s new? The symptoms? Have you done any data logging? A log replicating the event might be helpful. Is this only at wide open throttle? Does the car drive normally at part throttle conditions?

[MSMS3]

Originally Posted by SP1988 Thanks, the car is low km and the AFRs looked good but I'll check it

We are meaning fuel rail pressure value from the high pressure fuel pump, not AFRs. The ECU will make the injectors stay open longer if rail pressure drops (up to a point) to try to maintain a safe AFR. So it might look good. We need you to monitor fuel rail pressure under wide open throttle from 3,000 rpm to redline. And this needs to be logged, since a drop in rail pressure followed by recovery is often too quick to see on a gauge or live streaming.

[SP1988]

The problem is new, it has nothing to do with the tune. I didn't log it, but I did monitor a few different paramaters and it all looked normal.
I will have a look at the fuel pressure, it's not my car just looking at it for a friend.