Can't Boost over 14psi all of a sudden!

[unfrgivn]

So I have been running my FPBig28 at 1.3 Bar for awhile now with no problems. Then all of a sudden today I notieced that it wasn't boosting anywhere near that. I could only get it to go to 1 Bar and then hold. I have a profec-b spec2 and a greddy elec boost gauge and they are both reading the same thing from different sources so I know they are accurate. I checked and I don't have any boost leaks that I can tell, and the car build boost fast and holds nicely, so it's almost like the car is running perfectly (but set at 1 Bar). I tried putting my MBC back on the car incase the solenoid was messed and the MBC set almost at the highest setting, was still only boosting 1 Bar.

Occasionally I hear a soft rattling at full boost for the last 2000rpm before I shift, but not always. I don't think that was consistent or related, but I think there might have been a real quick noise. I am wondering if maybe the wastegate actuator could be messed up like the spring softened up over time or something else? I am really out of ideas, I tried all of the obvious.

Thanks.

[Var]

could be your actuator started leaking. If you dont mind..how do you like the turbo? what other sr setups have you driven? how does it compare? did you buy the stage one kit? you are the only one i know of that has the fpbig28.

[unfrgivn]

I love th Big28 as a cheap daily driver turbo. Doesn't have the quick spool of say a GT28RS or the power of a GT25/40R, but I think it's a healthy medium and it's only $750. Plus it drop right in with NO modification whatsoever. I am very pleased with this turbo and I have driven similar cars with the GT25/40R, T3/T04e, and S15 T28.

E-mail or AIM if you want to talk about it, I don't want this to go off topic.

[kcolyer27]

My friend has a problem with his big28 also. he is loosing boost after it hits its peak it will never stay there (20 psi). Check for leaks. Intercooler and shit might have a leak.

[unfrgivn]

My friend has a problem with his big28 also. he is loosing boost after it hits its peak it will never stay there (20 psi). Check for leaks. Intercooler and shit might have a leak.

Intercooler and piping all looks good. No leaks that I can find. There might be some appearing under boost, but like I said the car is running real strong. Also I have no problem holding boost, I can hold full boost almost to redline (~7000rpm), I just can't make more than 1 Bar, no matter what I try. Up until Saturday, I was running 1.3 Bar no problems, always built boost nicely and held strong.

I am thinking of ordering an HKS wastegate actuator on Monday, because I suspect that the actuator is the faulty part.