9 replies to this topic

[Privatealpha]

Took the car out to the Townsville drag way last night, and halfway though a run i lost half my boost pressure.
Next morning (this morning) I go out hunting to see if i have a boost leak, and tighten all clamps etc...
The car still doesn't go over 5 pounds of boost (12/13psi normally).
If there was a boost leak, i think the car would still make 12psi but much later in the rpm.
I'm always paranoid about low compression especially after a thrashing at the drags, but the idle is steady at 19 inches of mercury, no smoke, clean oil and water.

Checked the boost controller and lines and everything seems to check out.
No hissing noises that are immediate.

Only thing I can think of is the waste-gate or actuator stuck open.

Any ideas on what else to check for?

Thanks

[starlet666]

what sort of turbo are u running these days? because its well known that the smaller frame things that came on most toyotas have weak and flimsy actuators and it is possible that it has a weak gate or a stuffed diaphram

[Privatealpha]

Im running a Garret GT2560R (Silvia S15 equivalent), less than 1 year old.
Had a look at the actuator, and I can't move the actuator at all, seems to have jammed.

[BIG_FLY]

Could be your problem there then.... but a stuck wastegate usually means you don't make boost at all if not just a little bit,

[UDLOOZ]

if you have disconnected the diaphram and you still cant move the connecting rod to the actuator you definately have an issue... Turbo off and time for a rebuild or throw a new one at it

[Privatealpha]

After about 4 hours off fiddling around.
Found the problem.
The wastegate flap/door is loose, there is a lot of play so it is not seating correctly.
As a temporary fix, i shoved a clip in there to hold it tight.
It WORKED...for all of 5 mins and then I lost power again, the C-clip must've fallen out.
Doesn't bother me as i just wanted to see what the problem was.
Illustrated on Paint, exaggerated slightly.


How the hell does this happen?
Is this at all fixable?
Makes me really want to move on to an external wastegate.

[Privatealpha]

Dropped the exhaust from the dump pipe.
Loud as....loud, can confirm its not an exhaust problem (clogged).
Sorry to the neighborhood for listening to what appeared to be an obnoxious Corolla driving around with no exhaust pipe.

[UDLOOZ]

i had the same thing happen to my tdo5sh just binned the turbo and got another one..... You could just weld it shut that will sort the bleeding boost issue out haha

Props to you ms paint diagram to haha

Edited by UDLOOZ, 21 September 2010 - 07:56 PM.

[Privatealpha]

Yea theres no way i can afford to fix the car right now.
You should buy it, replace the turbo and you could potentially have a 13 second Corolla, now who wouldn't want that?

PM me if anyone has a cheap T28 they want to sell.

[Privatealpha]

New turbo on.
And the car finally has some performance again.

Looking at the old turbo, honestly cant see whats wrong with it.
Theres no play anywhere, no cracks that i can see.
Anyone have a clue as to why the turbo just wasnt running?
Probably hard to determine without looking at it though.