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Vct Setup On Rb25det

Harry50601

By Harry50601,
in Engines & Forced Induction

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89CAL Grand Master

89CAL

Posted
Posted

The most likely cause is the ECU spazing out at the increased boost and doing some R&R to save the engine

I'd be very surprised if its a VCT issue especially seen as it wont be working at the RPM you have mentioned anyway

My thoughts are unhappy stock ECU or coilpacks breaking down

Franko07 Enthusiast

Franko07

Posted
Posted

I'm not sure about the flat spot thing mentioned but my car does the same thing since lifting the boost up so I'm interested to see if the VCT is the cause?

But if you want to test this i would suggest just unplugging the vct at the head going for a drive (as i believe it only works when in gear, not idling) then plugging it back in and see if it makes a difference.

I think the reason they don't want you to join straight to the battery is chances are you will use the wrong gauge wire without a fuse and shit will get hot and it's just dodgy having something permanently powered when the car is off unless its a memory function for something.

89CAL Grand Master

89CAL

Posted
Posted

VCT does not stop working when you bump the boost up.

If you have a stock ECU and increase the boost then have problems with power/engine cutting out/engine feeling doughy, then the most likely cause is R&R, built into the ECU to prevent an accidental overboost from destroying your engine. It's not a case of it being 'sensitive' to boost, the car was designed to run 7psi max, so the ECU takes a better safe then sorry approach when it calculates airflow exceeding that.

Unplug your VCT, see if it feels worse, if it does then its definently not your VCT.

It will be the ECU

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