When going through the rpm range for the first time since the engine was cold, everything works like normal; 4500 switch over and everything's good. After that first time of switching over though, I don't get any boost until switch over and then it comes on like a beast. It will stay like this until the engine has completely cooled down.

It feels like a wastegate is stuck open or something, so I crawled under the car before and after, and found that my Turbo Control Actuator is stuck open afterwards, but not before. Does anyone have any ideas about what could be causing this?

Don't know why it would matter, but I have BNR Stage 3's and am using a Power FC

 

Anyone? Please?

 

Could be a few things, and I'm stabbing in the dark here.

1. TCA diaphragm is bad. Replace.
2. Interference between the manifold casting and TC flap that is resolved when the manifold cools down and shrinks back.

Best to run through the Turbo Troubleshooting steps on www.fd3s.net

 

The solenoids have been known to stick when they get hot, so maybe the TC solenoid is sticking.

 

Thank you for the responses. I will definitely go through that entire trouble shooting technique.

How do I test to see if the solenoid is sticking. Obviously I don't want to boost and go that high in the rpm range on a cold engine.

 

Tag - I"m having a similar problem. But it is not heat related. I can hear primary venting to the atmosphere until 4500 rpm - then it seems like both turbos kick in like a monster.

I cannot for the life of me figure out where it's venting. I've checked both relief and bypass valves, charge control, TCA, all major lines on Y-pipe, etc. The CCV must be seeing the primary boost or it would not open..correct? so where does that leave an opportunity for my problem?...going out to the exhaust maybe...wastegate or pre-spool.

 

If you can hear it venting and it kicks in hard, I would suspect the CCV. Run the KOKO test and see if the CCV (CCA) cycles as it should.

Dave