so heres the story.....


a few days ago, one of my tires got a flat and had to run on a spare for a few hrs because it was late at night and i was in the middle of the desert.. anyway, i heard a whirring sound from the engine bay and saw my oil level was low, so pulled over and got a few quarts of oil to hold me off until i got home and the whirring went away. keep in mind i did not build any boost on the way home since i could only drive 50 mph the whole time on the freeway and the next day i got the oil changed and drove the FD around and noticed something different....


the boost builds up slowly until around maybe 4000rpm then the secondary turbo kicks in hard as it usually does, but boost does build on the primary side. i am wondering if the turbo is blown or if theres another problem at hand. at WOT it sometimes does reach full boost JUST before the secondary comes, usually in 1st gear, but it is very slowly. it just is not as responsive for running 99 spec turbos sequentially. any ideas on what it could be or how can it be repaired? its just so frustrating because it was running so beautifully before and 99 spec turbos can be pretty pricey.....

 

Try this site for debugging the sequential turbo control system:

http://www.autosportracetech.com/RX-...leshooting.htm

 

ok thanks.. ive seen that page before and ill check through it again, but was wondering if anyone knows exactly how a blown turbo behaves, or maybe it could be a malfunctioning boost solenoid.. maybe someone has further insight....

 

Do you have a boost gauge? Are you sure it's building full boost on the secondary side?

If so, then you might have a problem with turbo pre-control.

 

if ur primary is shot, wanna sell ur secondary?

 

i doubt the turbo is blown...u would have smoking signs and such first I would think

If your secondary was kicking in and pulling hard as usual that would mean both were running strong because the secondary is the same as the primary and it would not pull hard at 4000+ if only one was working

 

i have a blown turbo and my car smokes out the exhaust like no other and strong oil smell

 

alright.. so no smoke coming out the exhaust and yes it does pull hard in high rpm.. if it is the turbo pre-control, what can i do about it to make it run better? go non sequential? any other options?

 

Get a boost gauge and go back to post #2 and read carefully...

 

i do have a boost gauge and it is reading full boost at high rpm.... ill chech that link and see what i can figure out... thanks guys

 

still trying. maybe the pre-control is stuck open? how could u tell this?

 

I have had the same problem before, I beleive this problem occured for me when i spiked over stock levels to about 14-15psi on a cold night doing hiway runs.
For about 2 weeks after i couldnt really build boost on my primary, no smoking ....
I beleive it was one of the Turbo control actuators....

Everything works pretty good now, just becarefully when your really boosting.. mind you i dont have an aftermarket ECU and no boost controller..
I am running full intake and CAT BACk exhaust with DP so i watch my Boost guage very closely when im boosting. I rarely just jump on it and WOT right away i let my boost gradually build up and then stomp it when im around +5 and it doenst usually spike that high...

 

okay, so its been a lil less than a week and it actually started spooling up faster and faster to now its back to where it was originally. i guess it just got stuck and had to be freed, possibly? anyway, its back to running properly just strange how it could happen like that... thanks everyone that tried helping out, now since i dont have to go replace anything, back to modding...... lol

 

just an FYI, if the pre-control was stuck open, your turbos would act like the wastegate was always closed... i know from first hand experience. great way to pop a motor as well

 

go single

 

.....if you have ten or fifteen grand to spend on the system, all supporting mods/hardware, and installation.

 

Just FYI. Typically, a problem that comes and then goes away on its own, will come back again eventually.