Thoughts..? Stuttering on Boost!
 

Hey Guys

I just installed a VF28 STi turbo onto my MY99 wrx. Also installed a new exhaust as the old 3 inch was rusted out. While installing this I also put a new genuine O2 sensor. Since installing the VF28 my car stutters on boost. The idle is smooth, not erratic at all. No different to before the install but as soon as I hit boost the stuttering occurs. What are peoples thoughts..?


Cheers

Has it been tuned since the install? Be my first stab..

Not tuned but I didn't think the VF28 was a huge upgrade over the TD04. Hence the MY99 ECU would relearn the new parameters.

What sort of condition was the turbo in? Ie the bearins, fins?

AFM is a possibility.

Computer to suit would help.
I changed from a TD04 to a VF35, but changed from a MY00 WRX ECU to a V6 STi ECU.

No play, fins undamaged. Can hear it spooling on boost.

[QUOTE=Tony;779405]What sort of condition was the turbo in? Ie the bearins, fins?[/QUOTE]

Might have to get my V5 STi ecu installed aswell but will try a few other things first. Like AFM...

[QUOTE=Saint_23;779407]AFM is a possibility.

Computer to suit would help.
I changed from a TD04 to a VF35, but changed from a MY00 WRX ECU to a V6 STi ECU.[/QUOTE]

[QUOTE=Saint_23;779407]AFM is a possibility.

Computer to suit would help.
I changed from a TD04 to a VF35, but changed from a MY00 WRX ECU to a V6 STi ECU.[/QUOTE]


I had same done to my MY00 thanks to Maximum Motorsport.

VF24 turbo, swapped ECU to V6 STI ECU (couple of wires to be swapped over).

Goes like a mofo!

In my previous wrx (97) it did this, would cough on boost had me worried might be map sensor.
Got in there and had a look, gave it a clean... Good as new.
Might not be this, however was a simple fix for a similar issue so I thought is throw this in here.


using the Perth-WRX mobile app

Too much boost? Injectors not keeping up?


using the Perth-WRX mobile app