Took it out on the highway last night, hasn't been more than a few weeks since most of my mods have been done. Running it through third I noticed my boost would hit about 15-16lbs and then start tapering off till the top of third to like 10-12 lbs. Does this sound like a leak or is this completely normal? It shouldn't have anything to do with excessive Iat2's and timing being pulled as I have made sure the intercooler pump is still running coolant through the heat exchanger. Could it be a vacuum hose or even a faulty boost gauge? I can't really tell but it doesn't seem like it's losing power (nor gaining super hard).

EDIT, UPDATE: Found out what it was: Torque Management was left turned on in the tune..... Pulls harder than ever now and I'm hitting just shy of 17 lbs in 98* weather.

 

My boost never declines in third gear while the RPM's are increasing.

 

it should deff. not being loosing boost like that. our cars build boost as the rpms climb and usually peak in the upper rpms and hold it till redline. sounds like you may have a boost leak. did you mess with the intake manifold to supercharger gasket at all when you put your 2.8 pulley on ??

 

Belt slip?

 

I didn't damage it, I was gentle as could be if that's what you were referring to, maybe a new gasket is needed if that's the case?

 

 

That's what I'm thinking, but it should be way more audible, right?

I am running the stage 2 belt

If it's belt slip should there be signs that I can look for?

 

you should be fine with a 2.8 pulley and stage 2 belt. is it a brand new stage 2 belt ?

 

Yes sir! It looks like it's snug on there.

So I'm guessing by looking at previous posts and threads that I should try Boost Bypass mod to make sure the solenoid is not kaput.

 

yeah that would be a good place to check. let us know how you make out.

 

Will do, gonna check it out tonight, really get it at it tomorrow to see whats up

 

I have seen this a few times. It usually ends up being a problem in the tune.

 

I can check that out tomorrow too, if I do the boost bypass mod temporarily just to check and that's successful at giving me boost back at wot, then it means it's just a bad solenoid or something in the tune, right?

 

Since boost is mechanical, I don't believe it would be in the tune. Check for vacuum leaks. You can always spray carb cleaner around the sc to intake manifold and around your vacuum lines to see if you're getting any leakage.... but... if you're getting 15-16 lbs of boost then you probably don't have any vacuum leaks or you wouldn't be getting that kind of boost to begin with.

Sounds like a actuator issue. Do bypass mod first. Then look elsewhere.

 

Awesome, I'll post back and let you know what happens when I do the bypass mod

 

Boost bleed is controlled by the tune it is not just mechanically controlled. If the actuator goes out it can cause the problem, but my guess is that the tune is bleeding boost.

 

Actually it sounds like belt slip I noticed it at the top of second too, went down to 13 lbs or so after hitting 16lbs, you could hear it stutter, my guess is if it was just regular boost bleed you shouldn't hear any fluctuation in the tone from the supercharger

 

Found out what it was: Torque Management was left turned on in the tune..... Pulls harder than ever now and I'm hitting just shy of 17 lbs in 98* weather.

 

I figured it was more than likely that or a setting in the boost control that was causing it