Smart people. Need your help. I'm not a tuner so bear with me.

My car was getting tuned yesterday but we did not finish it because 3port was. Not communicating with the ECU. Tuning the car through the ECU but when we hit 14PSI, waste gate opens. The ECU is not doing its job.

So, I did a quick test to see if theres a problem in the wiring/ harness. I unplugged the EBC and drive the car around. Sure enough CEL lite up. I plugged it back, CEL disappeared. So I know the wires work. I double checked the vacuum hoses and the are connected the right way per instructions.

I called Grimmspeed and they suggested to test the EBC using 9 volt battery. If it clicks, it's working. Sure enough, if works.

I'm about to put my old 2002 Greddy EBC just to get it tune tomorrow just for the sake or finishing the tune at the dyno. Old technology and can only go up to 24PSI (we have more room for more boost)

What do you think is wrong? Why is the 3port not talking to the ECU nor doing its job? Is there anything you guys can help me or have suggestions to my tuner?

 

Countless Of us run a GS 3 port. If you can confirm that the 3 port functioning per their instruction my guess is it is not being set up properly in the mapping or it is not installed properly.

Does your tuner have any experience tuning an Evo with a 3 port?

 

He tunes a lot of even but the minority's of of the cars he ties are STI and they had 3ports.

 

Most likely the vacuum plumbing should be looked at. There are multiple ways to set up the EBCS. Also plumbing will vary depending on if you are using an internal or external gate.

 

^ that