k this miggght be a lil long...i just installed a apexi gt exhaust on my ix mr. Before i installed this exhaust i still had a boosting problem. with the stock exhaust the car would only boost 1.0 bar maybe 1.1 i remember when i got the car it full boosted 1.3...now when i go wot the boost would sometimes (rarely) hit full boost if it did it instantly would drop to 1.0 bars and taper down as rpms rise. now with the new exhaust it boosts harder but not much i still have the problem obviously. but now with the exhaust i can hear almost a gargle or light poppin when im at full throttle and when the car should be at full boost.... im not sure if this is supposed to happen or if it could be the boosting problem. what do you guys think is wrong with my boooooost? thanks

 

do a boost leak check, that should solve your problem. i can't stress enough how important it is to periodically perform these to keep your car running good. even from the factory with nothing changed, there's probrably leaks, especially if you're only hitting 1 bar!

 

i did one once and i could only pressure the system to like 10 psi and it wouldnt go any farther... im brand new to turbo cars is there a certain process you have to do?? or do you just stick on your tester and pressurize?

 

anyone?

 

here you go http://www.vfaq.com/mods/ICtester.html

 

Your explanation of your problem isnt worded very well, so I am having a hard time understanding what the problem is. Is the boost lower than what it should be? Is it the noises your describe?

 

hopefully either your tester or compressor have a control valve, if not they're like $10 at home depot. then pinch off your boost control hose coming off the turbo compressor and sometimes(depending on where your internals are when shut down)air'll leak from your breather hose, so pinch that off or rotate the engine to close all the valves, then pressurize to your desired level with the throttle blocked open. listen and look for leaks. fix. you're done.

 

i had professionals check my car for boost leaks and they found my stockish car had one on the OE injector seals of all places!! my guess is i've always been leaking from the factory and would have never known.... which would explain my erratic boost

 

I think we should have a permanent banner on the main page stating the #1 rule to troubleshoot the evo "DO A COMPLETE LEAK TEST BEFORE ASKING ABOUT BOOST PROBLEM! DAGNABIT". Yup. In BOLD type too :P
And quit adding parts when you have a problem that is not fixed. Sorry, I am not trying to be mean.
Gargle/Popping usually means you have a leak in the exhaust stream.
And where did you get the BAR reading from? Where is your boost sensor (for this gauge) tapped into? Have you verified its reading against another gauge/sensor?

 

make sure that the intake snorkel (the little scoop that feeds air into your panel filter on the factory intake) is bolted down. If it is not bolted down its possible for it to suction cup itself to the bottom of the hood, and you will experience the immediate drop off in boost. There should be 2 screws holding it down. If its boted down and no screws are missing, I'm going to go with +1 on a boost leak test

 

I think he'd know if this were happening. The car almost face-plants when the snorkel gets sucked up like that.