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2000impreza
10-11-2002, 11:32 PM
asking for a friend. he has problems holding steady boost. jumps +/- 2-3 psi constantly. changed the wastegate and still does it so its not the wastegate. anyone have any ideas?
turboMiata
10-11-2002, 11:34 PM
Does he have a vacuum leak?
2000impreza
10-11-2002, 11:45 PM
not sure if it is a vacuum leak. the engine has a pretty steady idle

when the car sits for awhile... it will hold boost first couple runs but after that boost guage goes nuts.
95TsiAWD
10-12-2002, 11:55 AM
time for my favorite quote "Do an intake leak test". Preferably with the engine hot since that's when you're having problems.
Redlyne_mr2
10-12-2002, 11:58 AM
Originally posted by 95TsiAWD
time for my favorite quote "Do an intake leak test". Preferably with the engine hot since that's when you're having problems. :werd:
legendboy
10-12-2002, 02:41 PM
shit! oh wel, at least he has an adjustable wastegate now!
theken
10-12-2002, 03:36 PM
mine does that too it drops from like 7-8 to like 3-4 after i use my turbo like crazy it will drop down till i cool it off it is very annoying sometimes, i think just because the turbo gets pretty damn hot, i don't know though but it sucks:dunno:
rage2
10-12-2002, 09:38 PM
I've been getting boost creep the last week or two. One of the days I had unlimited boost...

Finally took the wastegate apart today, and the center section was sticking. A new wastegate (Tial), hoses and a few hours later, stable boost once again! Thanks to Marc for the weekend job, and soloracer for having an extra Tial sitting around :D.
Hollywood
10-15-2002, 01:40 AM
Originally posted by 2000impreza
asking for a friend. he has problems holding steady boost. jumps +/- 2-3 psi constantly. changed the wastegate and still does it so its not the wastegate. anyone have any ideas?

What kind of boost controller does he have?
2000impreza
10-15-2002, 11:40 AM
blitz sbc. but i don't think its the boost controller. he ran it straight off the wastegate and still did the same thing.
rage2
10-15-2002, 11:46 AM
I did the same tests on my car, pressure line running right onto the wastegate. Took the wastegate apart and the center section was sticking, which will give you nice boost creep at higher rpms. It'll get worse and worse until you get unlimited boost =).

Take the wastegate apart and press against the diaphram without a spring, see if it's smooth or not.
legendboy
10-15-2002, 01:14 PM
oh, and make sure that you brace the wastegate when your taking it apart and don't have your face directly over top of it and pop the lid off so it hits you in the mouth and theres lots of blood...etc...;)
DSM Power
10-15-2002, 02:22 PM
Depending on the turbo, even the best boost controller will spike slightly before being able to hold.... what kinda turbo is it?
2000impreza
10-16-2002, 09:17 PM
turbo is some sort of T3/T28 hybrid with modified compressor wheel. i think he has most his problems figured out..... swap a brand new turbo in. lol.