HELP!! Turbo Boosting when it wants to...

[Boostin2High]

Im havin some trouble with my turbo. It only boosts when it wants to, although my boost guage will read full boost. Sometimes it will do it in 2nd gear, or in all the gears..i cant figure it out...maybe its blown?

Some 1 ### help!

 

[Boostin2High]

Anyone?

 

[rich3389]

Have you done a boost leak test?

 

[Boostin2High]

no i havent...that was my next step but never have the time...the wierd thing is half the time it will boost perfectly....

 

[MrBoxx]

You need to give us WAY more information than "it's not boosting right".

By boost gauge, do you mean an aftermarket boost gauge, or the stock one? What is "full boost" for you? What kind of boost reading does your gauge give when it's acting up? Is there any turbo shaft play? Any funny noises coming from anywhere? What are you using to control boost?

And as mentioned, do a boost leak test and let us know the results.

 

[Boostin2High]

yes aftermarket boost gauge @ 15 lbs, mbc, no shaft play, no noises
no boost leaks to my surprise...but alot of white smoke at idle and at WOT

 

[ILLiCliPSE]

is your bov recirculated?

 

[Boostin2High]

Always.

 

[tylermartindc]

If you don't have a logger yet, I would suggest to pick one up and log some cruise and wot runs. My car felt like that before and it was because it was knocking like a sob, and I had no idea. It spooled up fine and all as you described, just it went no where. The ecu pulls timing if it sees knock, and the more knock the more timing that gets pulled. Which will make the car feel like a slug. It also might not even be real knock, just a bad case of phantom knock caused by a vibration or "noise" in the engine that the knock sensor picks up and thinks is real knock. My suggestion would be have a look at the sensor or do some logging.

 

[Street_Killer]

You should try and explain the problem a little better, but my guess would be a ripped spark plug wire thats only working when it wants to.

 

[Boostin2High]

as sad as it is to say..i have absolutely no idea how to use a logger and dont know were to find the knock sensor...and my plug wires are about a month old...

 

[Boostin2High]

also were can i get a logger and roughly how much?

 

[Street_Killer]

You can get a logger at a number of places, I recommend to get one at digital tuning because they are well known.

 

[mach4g63t]

I had this problem before as well. It wasn't, to me, that the turbo was spooling when it wanted to, but more like the turbo wasn't making as much 'noise' when full boost was achieved. And also, when I would release throttle, the BOV sounded as if it wasn't purging as much air. I wrecked the car but I fully figured it out, but I did check the Wastegate as well as a Boost Leak, and it was neither. In addition, I did remember noticing that my compressor shaft had LOTS of play. That's when I first learned of the whole shaftplay/bad turbo thing. I was also running an open-atmosphere setup without MAFT. I had just the stock boost gauge so I wasn't able to tell what my PSI was. It should've been stock, and while the gauge was junk, sometimes it would max out, and other times it would be just shy of the top of it's gauge travel. It was like sometimes the turbo would go, boost full, purge loud as hell (Type-S), and other times it was struggling. I'm just curious...

 

[Boostin2High]

See, thats the wierd thing is when it does work..it screams..when it doesnt, it sounds N/A..

Something new happend today... I pull out of my driveway, 1st gear i shifted at like 5000ish seen no boost , 2nd gear shifted at about 71 - 7200 had no boost untill i hit about 5700 rpms at WOT. And it kicked in like i never felt it before..but mean while, while i have no boost im looking at my boost gauge to read psi..its reading normal!! and it was the same way throughout all my shifts....

any suggestions?

And im sorry if its confusing...if you need better explaing dont hesitate to critize ...im not good at explaining actions.....

THANKS!