What would be considered "sustained" boost?

I hear the term used, but I'm not sure what my expectation should be for staying power.

I can feel, hear and see the boost build at WOT, but it is not lasting-quick thrill.

I can hit 6,7,8 but then it drops off quickly--less than 2 seconds on any number before dropping.

What is the standard?

 

2 seconds is really short - sorry. However if you get sustained boost for more than 4 hours, you need to get to a doctor fast!

 

Yep no 4 hours here---what could be the cause of short boost duration?

 

You should not be droping boost like that. If it's hot out you will not be boosting the same obviously. But you may have a boost leak.

 

thanks! how do I check for boost leaks?

I had the intercoolers off for a plug/coil swap, but everything "click" tight and seemed good. Were else can I get leaks?

 

Search for the thread on a build-your-own boost leak tester.

I strongly recommend that you get a Durametric and log some data. It will be a lot easier to sort out. I'd suggest logging rpm, boost pressure of sensor, set point boost, engine load, O2 lambda sensor values, MAF and ignition angle.

I'm not a real expert at this, but I think that a boost leak would show up as a significant difference between set point boost (target) and boost pressure of sensor (actual).

 

before this , were you holding boost just fine ?

 

No difference that I can recall. I did this right after I bought the car last year.

 

So its been like this the whole time since you bought the car ?

let me get this right, the car boosts say .9 bar and then as your going through the rpms it drops down to .7 bar ?

 

yes-- on any number above .5--it spools up quickly then drops off just as quickly.

It still has some boost but it will drop from .8 to .5 or from .6 to .3 within 2 seconds.

It just seems like it should maintain the higher boost for longer.

 

there is something deffinately wrong, a healthy car should maintain .8 bar all the way through rpms .

get a boost leak test. you have a leak somewhere.