MrHH

Hello guys, i have a Greddy turbo kit on my car. And whenever i try to boost or even at vacuum. the boost guage flutters. I personally think its a boost leak.

Does anyone know a way to check for a boost leak on an rx8 with a Greddy Turbo kit? i cant find anything

9krpmrx8

iTrader: (46)

Flutters or is all over the place? Have you checked the pipes and couplers? How are your AFR's? Do you have a blow off valve? Do you have a boost controller? is your car Cobb tuned or running the E mangle?

MrHH

Flutters
I checked all my piping can't seem to find anything wrong.
I have a blow off valve
Yes I have a boost controller
My car is COBB tuned

Let me get back to you on the AFR because I didn't check that yet.

This all happened after awhile of driving and got progressive worse.

MrHH

AFR Normal

Carbon8

iTrader: (4)

Describe normal?

MrHH

11.2/20.3

RIWWP

iTrader: (2)

I don't think you have a good grasp of what AFR means...

You just stated the min/max range of the sensor, not what AFR you actually have.

MrHH

Do you want it at idle? 11.2 is under full throttle.

At idle it bounces from 14.8 to 15

Carbon8

iTrader: (4)

Progress

Seems a little rich, but within acceptable range

MrHH

So how do I test for a boost leak

9krpmrx8

iTrader: (46)

It's not rich if he is under boost. I still don't understand how a boost gauge flutters? Are you talking about an audible flutter from the turbo or your boost gauge is fluctuating. Also what kind of boost controller do you have and what are its settings?

MrHH

my boost gauge literally fluctuates. It bounces around and is not steady at all. It's not smooth, it jitters if that makes more sense

I have a mechanical boost controller

9krpmrx8

iTrader: (46)

Ohhhhh, well either your boost gauge is jacked or your MBC is a POS. You really should get an electronic boost controller wither way.

RotaryMachineRx

iTrader: (1)

Run without the Boost controller if you can and see if it does this, what BOV are you using and is it VTA or Recirc? does the car bog down at all when you floor it or does it accelerate to redline smoothly?

jayrerickson

To me it sounds like it is a BOV or Boost controler.

A boost leak would show more on your AFR and you would know just from the drivablity. Even with a small leak, it would run like crap (1/4 run that is) and you AFR would be off.

First I would check the boost controler. Like most, it is a ball and spring set up. Some have a bleeder hole and some dont. The bleeder hole is to help with the fuctuation. The spring in allmost all MBC are weak (even some name brand), you can find quality ones if you look hard enough.

I always made my own. You can set the spring tenstion to your set up. If it is to weak, it will flutter like you are talking about. It it is to stiff, it will not open and you will over boost. Get it right, you will have a great run.

RotaryMachineRx

iTrader: (1)

We still dont really know enough from the OP to pinpoint exactly what it is but from the little we know I wanna say 1 of these 4:

1. Boost Controller
2. WG actuator
3. Boost Gauge
4. BOV