Boost Problems. Tried almost everything.

[infinite_kaos]

Ok so I am having a problem with getting the proper boost on my car. I have tried so many solutions to fix the problem and still no change.

Here is the issue:

Cant boost above 7 psi.

I have an MBC and when I adjust the pressure, or rather try to adjust the pressure, nothing happens until the MBC is fully closed then it spikes up to above 20 psi and I immediately let off as I am not set up for that pressure at the moment.

I have BLT'd to no end and have come up sealed tighter than a bank vault.

New plugs.

New gaskets for exhaust side.

Put my 16G back on as I thought the t25 was going out and causing this issue. t25 was fine.

Timing was previously off one tooth on the exhaust cam. I redid timing and still the issue remains.

Compression test (when cam was off a tooth and I was unaware) from 1-4 170, 170, 170, 145 put a cap full of oil in number 4 and it shot up to 180( I have yet to do a compression test since I redid timing but the boost problem has not changed for better or worse since then.)

Im completely lost on this and hoping that someone can shed some light on this situation. Im thinking maybe knock but I havent had a chance to check whether or not thats it. I can put DSMlink back in but Im trying to get the car to just operate normal stock (well except for the 16g and 255lph pump, reason for the high pump is because I thought my stock pump was going out causing a lean condition and pulling timing)

 

[GRAVEDIGGER]

What kind of boost controller are you trying to use? Have you tried another boost controller, or better yet, have you tried to go straight off the wastegate without a boost controller? I would think you could get at least 10psi going straight off the wastegate actuator.

 

[infinite_kaos]

From j pipe to wg I get between 6 and 7. With the bcs connected I get the same. The only time I get more is when I have no boost source to the wg. When I had dsmlink in it never had this problem. Could it be ECU?

 

[genegoesfast]

Sounds like something might be wrong with the wastegate actuator. Have you removed the actuator arm from the flapper and tried to move the actuator yourself? Im guessing it will be waayyy too easy to move. Just a guess.

 

[GRAVEDIGGER]

Sounds like something might be wrong with the wastegate actuator. Have you removed the actuator arm from the flapper and tried to move the actuator yourself? Im guessing it will be waayyy too easy to move. Just a guess.

Yes, that is where I would be looking next too, but the chance of the actuator or flapper door having a problem on both the t25 and the 16G is pretty slim, so

 

[infinite_kaos]

I checked the actuator before installing it. I had an external gate with atmosphere dump before I went back to stock. The actuator is stiff as any other actuator I've had.

My only option is to swap my link ECU back in and see if that's it

Just remembered that my rear mount is toast. Causing the bellhousing to rattle on the subframe. Could this cause the knock sensor to react and ECU pull timing?

 

[HULK]

Update? Did you find out why it wasn't letting you boost?

 

[dahawkster]

I am also having the same problem. I tryed 2 didferent boost controllers and tryed running off the wastgate and adjusting with the rod, its either to high or to low...

 

[keltalon]

My guess is definitely the wastgate.

 

[dahawkster]

infinite_kaos please lmk how you fix yours