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3S-GTE Hesitation from idle & Boost question


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I have my link ECU installed and the car seems to idle and run great now I'm over some initial hurdles.

The only issue that I have is that the engine bogs down from idle whenever the throttle pedal is pressed (once the rpms are above idle, it doesn't seem to be an issue).. I've tried pressing it fast and slow but it has the same affect.. The engine will dip from ~900rpm to ~700rpm before it recovers and accelerates. I've adjusted the Accel Enrichment deadband all the way down to 0.1ms and that seems to help a little when I press the throttle slowly but I can tell the underlying issue is still there and the revs still dip when I press the throttle fast. 

The other question is just to help my understanding. I can see that the Boost target is set to 200kpa but when I'm driving, I only see 150kpa maximum pressure.  I didn't see any boost target trim in effect so I'm not sure what the reason is here.  Any ideas?

I've exceeded some kind of forum limit for attachments so I'm adding the Log file here from my Google Drive.


Mr2-First start 1-24-23.pclx

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The hesitation is likely because you have no accel enrichment.  I would also suggest enabling async injection as it makes accel tuning easier.  

Start with the settings below.

The boost not reaching target is because your wastegate DC table is no where near what it needs.  I suggest you use open loop until you get the basic tune done as changes to the ign map etc will mess up any closed loop boost tuning you do.  When you are ready for closed loop there is a setup guide in the help file here: G4X ECU Tuning Functions > Boost Control > Closed Loop Boost Setup Guide



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Thanks Adam, those settings and values have worked wonders for my off idle acceleration.

It's going to take me more time to learn wrt the boost issue and what values to use for WG duty cycle but I appreciate the insight.  One last question - I was wondering if the Link ECU was even working with the stock Boost controller (TVSV) or if I was required to use a Mac 3 port EBCS.. I have a MAC EBCS, just haven't installed it yet.  I don't think the TVSV works like a normal boost controller so maybe it just isn't working with this ECU which is why I'm only seeing Wastegate spring pressure for boost.

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The factory TVSV is an on/off solenoid that basically sets two different boost levels with a factory turbo/wastegate actuator via a fixed bleed off orifice.  It is not in any way a tunable solenoid for boost control.  That said, I usually install Sumitomo style connectors on a MAC solenoid that will plug into the original TVSV connection and make actual boost control possible and plug and play.

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