I've got a stock motor/turbos with upgraded intake, I/C, and DP/HFC/CB. I thought that I might run into boost creep, but I've got the exact opposite problem. I set my boost to 0.75 in FC-Edit with low duty cycle to try to eliminate spikes. But instead, I get a 0.85 spike at 3000RPM that settles to 0.75 until transition (4500RPM) which then drops to 0.65.

Does this mean I've got a boost leak? The only place I could think of that could cause this would be the hose that connects the compressor outlet to the split-air bypass valve, or the valve itself. Is there some clever way to test this, or do I just need to replace the part?

I thought it would be boost creep that kills me, but it's boost loss instead...

-ch

 

You played arod and remapped things in your car. I've never used a FC but maybe you din't do it right.

 

Yeah, I know--but my question is: Where should I look for boost leaks related to the secondary turbo?

-ch

 

What did you set your base duty cycles to for both primary and secondary?

This should probably be in the PFC forum.

 

I set them quite low, as advised to limit overshoot. But since I'm seeing full boost on the primary but not the secondary, I am thinking it's a boost leak. What are the most common causes of boost leak when the secondary comes on line?

-ch

 

Check the Charge relief valve, the hose, and make sure the actuator is working properly.

If I had to make a guess.. I say its the hose from the secondary turbo piping to the CRV.. usually those get old and brittle.. tends to crack and loose boost..

hope you find the problem..

 

Have you tried setting your duty cycles to average values rather than low ones?

 

Go back to stock settings and see if you still have the problem. If problem persists you have a leak. If problem is gone get a prefesional to tune your PFC

Good luck