Bad Wastegate?

[mario009]

Hi everyone i have a 99 gsx and this is what happens. Ok.. Since i have an Automatic, when i floor it the boost gauge goes all the way up and then cuts off for a second bringing it down to no boost but then goes up again it almost feels like my tranny but i know its not cause i got a p1103 code and its invloving the waste gate also when sometimes when im cruising at say 25 mph i hear the turbo kick in but i dont feel any boost this actually happens wheni floor it too sometimes. Could this be from the same problem? I have the stock t25 turbo so if anyone can help ASAP that would be great. Oh yeah also i got code -p0420 and p0400 what are these and how do i fix them???

 

[blcknspo0ln]

if you're wastegate was stuck closed, you'd build an infinite amount of boost pressure

if you're wastegate is stuck open, you barely build any boost at all

 

[johnfsmith]

Hi everyone i have a 99 gsx and this is what happens. Ok.. Since i have an Automatic, when i floor it the boost gauge goes all the way up and then cuts off for a second bringing it down to no boost but then goes up again it almost feels like my tranny but i know its not cause i got a p1103 code and its invloving the waste gate also when sometimes when im cruising at say 25 mph i hear the turbo kick in but i dont feel any boost this actually happens wheni floor it too sometimes. Could this be from the same problem? I have the stock t25 turbo so if anyone can help ASAP that would be great. Oh yeah also i got code -p0420 and p0400 what are these and how do i fix them???

P1103 Turbocharger Wastegate Actuator Malfunction
PO420 Catalyst Effiecncy below threshold (bank 1)
PO400 EGR Flow Malfunction

 

[99gst_racer]

if you're wastegate was stuck closed, you'd build an infinite amount of boost pressure

if you're wastegate is stuck open, you barely build any boost at all

Minor corrections:

If you're wastegate was stuck closed, you'd build the maxium amount of pressure that your engine is capable of flowing your paticular turbo to.

If you're wastegate is stuck open, you won't build any boost whatsoever, unless you are creeping.

mario009 - Test your wastegate actuator to verify that is it functioning properly.

 

[blcknspo0ln]

fine. have it your way

speaking of which, if you're wondering how to test your wastegate, just hook up a bikepump to a vac line into the wastegate nipple. then just push down on the pump and you should see the wastegate arm move.

if it doesn't move, obviously your wastegate is messedup and won't open