All of a sudden there is no boost. How do I tell what is the problem. I wanted to take the turbo off and see if it was froze up or something but not sure how to get at it. I am thinking the turbo went out because it doesn't sound like it is spinning at all and the power sucks, can the stock turbo be rebuilt and who does that kind of work, If that is the problem what are your suggestions as far as replacing it with a stock turbo or getting something bigger and what kind of things need to be done for a bigger turbo besides tuning, like will it just fit into place or is there a lot of adaption needed? also what are the turbo models called to find another one like the stock numger or a bigger replacements id number. Thanks for the help!

 

check all of your vaccum lines, inlet, maf... and theres a few people selling td04s on her that are on good condition for a cheap price

 

does your car still have the stock uppipe? do you have a boost guage? if your getting 0psi boost then you might have sucked a chuck of cat into your turbo. if your building some boost but it not alot like only six psi then you most likely have a cracked vac line.
DIY: VF34 turbo on WRX (with pictures!) - ClubWRX Forum - Subaru Impreza WRX and STi Community and Forums
follow these directions to remove your turbo. when you get it out see if its seized. see if theres cat keeping it from spinning. ok so here is where the choice to upgrade comes into play. if you can safely remove the cat from the turbo and there is no shaft play and or other damage then all you have to do is replace the uppipe (180)and bolt your turbo back on. if you want to replace the turbo then you have alot more work to do. there are many direct bolt on turbos. aps, fp, deadbolt, ihi vf series just to name a few. when you upgrade the turbo you will have to upgrade the injectors(700), turbo(700-1300), uppipe(180), em(700), fuel pump(180). before you know it you have spent 3k on your car after tunning(120 an hour minimum of 4 hours) and dyno(60+) to see how much whp the new improvement is.

 

You need to determine if the turbo is working first , so see if the turbine is spinning and functioning....you can take off the downpipe and spin the wheel or take of the inlet. If it appears to be functioning then you need to do a boost leak test on the car and find any leaks. If you need me to do one for you then pm me.