Stuttering under heavy acceleration at about 4k rpm

[Ytee]

Hi all.

I'm betting someone's had this before and knows exactly what this is. I'm getting stuttering issues in my Mk5 under heavy acceleration when I hit around 4k rpm. It almost feels like a rev limiter kicking in, although of course it isn't that. Eventually it pulls through and continues on normally up to the red line. It's a bit sporadic, doesn't always happen, but it is fairly easy to recreate by accelerating with the pedal flat from about 2k rpm in 3rd, for example.

There's no EML, and VCDS brings up no fault codes either. I've recently changed the air filter just in case it was that, but no.

The car is standard except for a simple Bluefin remap, but that hasn't caused me any issues in the 5 years I've had it.

I fear it's the turbo, but, before I start sending it in for expensive diagnostics, I thought I'd ask here :)

[GVK]

Crank sensor losing signal.

[mjmallia]

Check a few of the obvious ones like fuel filter, spark plug condition, when was the last time you did a carbon and injector clean on the intake, boost leaks  and so on.

[Ytee]

Thanks for the replies Happy it sounds like a maintenance thing rather than imminent major failure.

Spark plugs are good I did those not long ago (and it didn't change the problem), but the rest yeh, never to my knowledge.

It doesn't feel like a boost leak, it's feels so "electronic", but of course I could easily be wrong, I'm not an expert. But the injectors is interesting because there is also a sporadic misfire at idle actually, and I've always wondered if that's a lazy injector. I'll have to look into the crank sensor as well.

[GVK]

Andrew Chapple of volkswizard YT channel had an ED30 with a similar fault and he had a crank sensor signal failure. He did have EML on and a fault code for crank sensor implausible signal though.

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[GVK]

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[Ytee]

Yeh, I've researched it in the meantime and it's definitely worth trying since it's such a cheap change. I've bought a new one and now I'm just waiting for an opportunity to fit it, so, fingers crossed and I'll post back either way. Thanks for the advice