yamaha

I was fine tuning my 18psi MAP tonight. Everything was working fine, I was getting the TurboXS boost controller set at 18psi. While I was messing around with it I was doing some highway pulls to get it set at 18psi. When I got back on the highway and did a pull the boost gauge showed it pulling until 15psi, then it dropped to 10psi. I got back off the highwas thinking that a vacuum line came off. I double checked everything and it seemed to be fine. I adjusted the boost controller back down some but it did not help at all. The turbo will spool fine, but it will build slow to about 8-9psi. What's strange is the blow off valve is also not working. Normally when the turbo starts to spool and I let off the gas, there is a flutter, but nothing. I rechecked the vacuum lines and looked around the engine bay real quick and everything seemed ok. Thoughts?

Thanks,
Sean

funkypc

So are you saying it wont boost over 10 psi?
does the engine feel like you have 15 psi of boost, or does it feel like less?
Its possible your BOV is leaking.
or, if your vacuum lines for the BOV and your boost guage are t'd into the same place, that could have come loose or undone.
or worst case scenario you blew your turbo.

supercow

check the wastegate.

funky whats that grey blob appearing behind the car? It's a ghost!

funkypc

lol, something subtle i did. It was supposed to be exhaust.
looks kinda ghey though shrug.gif

Jay-M

Two words.... Boost Leak!!!

SOCKS_old

sounds to me like one of a few things... but im wrong alot, so i duno..

your BOV could be leaking at certain pressure, or just have a small leak ALL the time.

you could have a coupler thats not tight enough and gives at a certain pressure..

your wastegate could be jacked up.. yes, thats my technical explanation 'jacked up'. do you have internal or external gate? if its internal, i know some aren't good for regulating boost after certain pressures.

if your BOV is not working when you let off the gas, then it may be letting all the air out while you are boosting.. what type of BOV do you have?

your turbo is fine.. its most likely a leak somewhere along the line..

o, and i duno how many people you told, but nice numbers for that car.. i wish i woulda bought it when i had the chance..

Denisst99

bov stuck partly open?

yamaha

I'm thinking that it is the BOV not working properly. I'm going to do a boost leak test when I get off work today to see if this will help.

SOCKS_old

when your car is idling, put your hand where the BOV vents.. if air is coming out, its leaking for sure..

again, which BOV do you have..

Alex01tib

I'd definatly think it was a boost leak from somewhere, charge pipe, vacuum line, BOV, IAC.

Do you have your intake temp sensor and or maf post turbo?

Oh god, i hope you didnt blow the welds on the intake manifold!!

Ok the last one might not help wink1.gif