Archangels

last year while i was at the track redlining 3rd gear all the sudden i heard a loud PSSHHTTT and the car lost power momentarily.... i pulled over, checked everything, seemed fine other then the turbo glowing red, since then anytime i go WOT there is an audible change with the engine/exhaust, it idles and runs perfectly fine but when i boost above 12psi the noise is present. NOT under 12psi or at idle and normal cruising, THEN it sounds normal....

i checked the entire car for leaks, and cant find a thing, put a boost leak tester on and cant get more then 12psi or so and hear tiny leak's from a few places, the only idea i'm left with is that the intake manifold gasket may be leaking (from the lower to block), the car still has a fair ammount of power, however, the boost is very inconsistant now and keeps climbing when i go wide open and does not maintain a steady boost, i'm pretty stumped, the car acts the exact same as it did before but now anything, again, over 12psi, the vehicle has a different, tone i guess you could say, to it and has boost issues....

any and all help with trying to find out what's wrong with my car would be greatly appreciated!, i'm stumped, i've even made time tommorow to get my car on the dyno and to get a few others to listen and hear where it's coming from....

Turbo II Rotor

iTrader: (2)

Glowing turbine housing and boost problems, did you melt your wastegate line?

dtale15

iTrader: (1)

thats one angry *** turbo you got on there. good luck lol

Archangels

by melting my wastegate line, do you mean the vac. source going TO the wastegate?, i put a boost leak tester on the car, if it was the vac. source wouldn't it leak when i pressurized the system?...

i found a small leak at my lower intake manifold block-off plate, but i dont think it's enough to make the boost fluctuate like it is....

gameover2145

iTrader: (1)

List of mods? Could you be more descriptive of the "tone change"?

Archangels

the tone change sounds like additional air is being forced into the exhaust, it's somewhat complicated to explain.... perhaps.... the tone itself has changed....

it's a new motor with RA seals, 4000km on rebuild, BNR3 turbo, and every bolt on possible with emissions removed.... also has knife edged TB, secondaries removed, ported upper and lower manifolds, etc....

the BEST way to explain the noise is that it has a leak somewhere that is adding noise to the exhaust, weither it's a vac leak, or leak in the turbo actuator....

after speaking with the local rotary shop, without seeing the car he rules out the engine being "done" or "blown", he said it's 90% turbo related, i have no leaks in my piping and he thinks it's the turbo's actuator leaking or not operating properly....

if i pin it in 4th or 5th gear the turbo flutters and the car surges, not sure if i mentioned this prior or not, but this leads me to believe there's a leak.... somewhere....

Archangels

i should add, because i'm still trying to put my finger on the problem, the car drives and start's fine, it's kind of cranky till it's warmed up but it's been like that since i can remember, after the track time the exhaust note is different, i noticed slowly that the turbo would take later and later to spool, i only noticed because i drove the car daily for a year, the exhaust note change is primarily when the car is at WOT and when i'm driving at part throttle, it is not noticible.

i'm kind of confused, it only happens when i have my foot on the floor, it drives nicely like it always has, technically with it starting normally, running normally, and driving without hessitation, could i rule out that the engine could be the culprit?, in the sense that i could not have damaged a seal or anything internally, and that my issues could have a finger pointed at the turbo?...

i called the local rotary shop, and although i'm leary with most of what he says, he did say it's 95% my turbo, with no leak's present (or very minor one's) when i do a boost leak tester, and doing the "poor man's" compression test with each "woosh" being audibly and forcefully (hand on port) the same, what do you guy's think?...

any and all input is greatly appreciated!, as always....

arghx

iTrader: (3)

Are you sure it's not an exhaust leak?

Archangels

i'm pretty sure it's not an exhaust leak, i checked over the car multiple time's, and even if it was an exhaust leak, it wouldn't explain the loud "PSSHH" i heard while at WOT and the inconsistant boost, could it?...