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Blown 2nd Turbo symptoms but 1st turbo doesnt recover?


Guest AirBear69

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Guest AirBear69

Hey everyone

 

I have a friend with a 2JZ-GTE VVTI swap stock with the sequential turbos FMIC kit running the stock 89661 ecu. It can build its 7psi no problem but at about 4,000RPM it sounds like the wastegates open up and the boost drops to 0. It will also happen if you rev the engine in neutral or if you go over 120KM/H. I am very new to 2JZ engines but to me it seems like a limp mode. The only way to get the boost to build again is to turn the car off and on again. Could this be a vacuum line issue? He has been driving it around for a wile now at 1/2 throttle.. Anything more seems to trigger this "limp mode". The research I came across seems to tell me the rear turbo is blown but the boost wont come back until the ignition is cycled..

 

Thanks

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7psi? is that 0.7 bar? :S

 

I'm no expert but sounds like one of the VSV's isn't shutting properly or something along those lines

 

have a read of this explaining the sequential system, might help you diagnose the problem

 

http://www.mkivsupra.net/vbb/showthread.php?35926-The-sequential-system

 

17psi is 1.1 bar I think - I dont know if that helps lol :)

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Guest AirBear69

Thanks for the replys everyone.

 

I will be sure to test the VSV in a bit. I just got home so Im going to check out a few threads on the sequential setup and how it works. I had found a vacuum line that was reversed on the VSV.. It was looped when he first got the car. I just noticed that the CEL comes on when it happens but the codes are always different. Usually body control codes. Nothing that would lead to the turbo setup but I could be wrong.

 

He is looking to go single turbo soon and I will most likely be doing the work but I would love to get the sequential working first to actually feel them pull. The swap is in an IS300 I will have to pull the motor to do the turbo conversion :(

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Guest AirBear69

Hey everyone...

 

SO tonight I did the TTC mode.. the car would build boost for a second then can't build boost at all. I pulled over and noticed when I unplugged one of the vacuum lines it was pressurized.. The one that runs to the actuator on the top of the motor. I let the air out and tried again and it built boost for a sec then dumps it. I blocked it with a screw and still dumps the boost. I left it unplugged and now the car can build and hold about 7PSI of boost. It spikes to about 10 and falls down to about 6-7. Does this mean the 2nd turbo is blown? Im starting to wonder if the vacuum lines that I cant see are connected properly :S

 

 

 

Thanks

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Guest AirBear69

Hey everyone..

 

So I wired the gates open and the car makes 0 boost. I also hear a little whining sound that I herd is the death whine so Im guessing rear turbo is blown. I have two other sets here but there is a bit of shaft play in them.. Witch turbos are the best for this setup? JDM or USDM?

 

I herd that the JDM have ceramic exhaust wheels... I believe his swap is the newer VVTI so I will have to check when I pull them.

 

Is there any other mod I should do to the twins besides wiring the two gates open before I reinstall them? I was thinking of deleting the EBC's and running MBC for now.

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Hey everyone..

 

So I wired the gates open and the car makes 0 boost. I also hear a little whining sound that I herd is the death whine so Im guessing rear turbo is blown. I have two other sets here but there is a bit of shaft play in them.. Witch turbos are the best for this setup? JDM or USDM?

 

I herd that the JDM have ceramic exhaust wheels... I believe his swap is the newer VVTI so I will have to check when I pull them.

 

Is there any other mod I should do to the twins besides wiring the two gates open before I reinstall them? I was thinking of deleting the EBC's and running MBC for now.

 

Are you forcing the actuators to stay open? IACV and EGCV...

Look what i did here http://www.mkivsupra.net/vbb/showthread.php?292015-Loosing-boost-when-2nd-turbo-comes-online. This way you force the 2nd turbo to have an exhaust and inlet access and will force TTC.

Edited by ryansupra
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Guest AirBear69

Hey Ryan

 

I couldn't find what you were referring to on the page..

 

I have wired the EGCV actuator so stay open by removing the actuator arm and wrapping wire around the flap to hold it open. I can hear a different tone in exhaust so Im guessing it worked.

 

Then I removed the C clip from the IACV actuator and wired that valve open as well.

 

Now the car will build no boost at all and in the higher RPM I can hear a whineing sound. When he first got the car it had one way valves installed so im guessing the guy who owned it before had it in TTC mode already and probably blew the turbo before selling it.

 

Before I pull the turbos is there any other thing it could be? Should I try unplugging the wastegates completely to see if it over boosts? Could this be a stuck open wastegate?

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Hey Ryan

 

I couldn't find what you were referring to on the page..

 

I have wired the EGCV actuator so stay open by removing the actuator arm and wrapping wire around the flap to hold it open. I can hear a different tone in exhaust so Im guessing it worked.

 

Then I removed the C clip from the IACV actuator and wired that valve open as well.

 

Now the car will build no boost at all and in the higher RPM I can hear a whineing sound. When he first got the car it had one way valves installed so im guessing the guy who owned it before had it in TTC mode already and probably blew the turbo before selling it.

 

Before I pull the turbos is there any other thing it could be? Should I try unplugging the wastegates completely to see if it over boosts? Could this be a stuck open wastegate?

 

OK, what you did was a valid test to bypass the actuators. So now you narrowed it down to 2 things, either a blown turbo or bad wastegate which i highly doubt. I would try unplugging the wastegate and see if the boost stays but beware that you might blow the the other turbo which sounds like it is still good. I am pretty sure that you have a bad 2nd turbo. When the 1st one spools up, the boost is just being lost through turbo 2.

 

My suggestion is to remove piping and inspect turbos.

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Guest AirBear69

Thanks Ryan!

 

I went ahead and started removing the piping and stuff and indeed there is oil in that valve box that opens the 2nd turbo :( So I was wondering if I could just remove the center section clamp and separate the turbo and swap the hole center section with another one I have on the bench? I have the heatsheild and everything off and it looks like I could but I don't know how hard it would be to separate the center section.. It took me air tools to separate a CT26 the other day :S

 

Also can I delete all this electronic shit? I want to wire the valves open the way I did and even remove the electronic boost controllers and run a MBC. Can I do this? I was reading I might need to add some resistors and stuff to trick the ecu.. I also have a diagram for two for a MBC install. Can I remove all the pressure tank and all this crazy vacuum system as well?

 

Thanks!

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Thanks Ryan!

 

I went ahead and started removing the piping and stuff and indeed there is oil in that valve box that opens the 2nd turbo :( So I was wondering if I could just remove the center section clamp and separate the turbo and swap the hole center section with another one I have on the bench? I have the heatsheild and everything off and it looks like I could but I don't know how hard it would be to separate the center section.. It took me air tools to separate a CT26 the other day :S

 

Also can I delete all this electronic $#@!? I want to wire the valves open the way I did and even remove the electronic boost controllers and run a MBC. Can I do this? I was reading I might need to add some resistors and stuff to trick the ecu.. I also have a diagram for two for a MBC install. Can I remove all the pressure tank and all this crazy vacuum system as well?

 

Thanks!

 

 

If you are planning on staying TTC, you can get rid of all the sequential components. ECU does not need any work or resistors as far as i know. Mine adapted to TTC on its own. Not sure why you prefer the MBC over an EVC. IMO, EVC is better as you can adjust boost on the fly. My HKS EVC4 has 2 settings, that way i cruise on 1 bar then crank it up occasionally.

 

Regarding the turbo removal, not sure how to help on that. I never had to remove min yet (fingers crossed)..

 

Where are you from in Canada?

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Guest AirBear69

Oh okay thanks

 

I had to pull the motor forward a bunch to get at the turbos... Im trying to figure out how I can rig up a boost controller to both the turbos.. If I tee both the both ports of the waste gates to an EBC, would that be efficient enough to control both turbos? Or would one turbo boost more then the other or something? I would like to put it all back in without all this messy vacuum system.

 

Im in Ottawa Ontario where are you?

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Oh okay thanks

 

I had to pull the motor forward a bunch to get at the turbos... Im trying to figure out how I can rig up a boost controller to both the turbos.. If I tee both the both ports of the waste gates to an EBC, would that be efficient enough to control both turbos? Or would one turbo boost more then the other or something? I would like to put it all back in without all this messy vacuum system.

 

Im in Ottawa Ontario where are you?

 

Since you are wiring the turbos in TTC, the wastegate is going to control both turbos identically. The Supra has only one wastegate that is on the first turbo. In TTC, all the sequential components are bypassed so both turbos are linked together. Once the wastegate on turbo one releases boost, both turbos slow down.

 

Did you manage to see the damage? I am in Brampton, Ontario.. Quite far from you.

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Guest AirBear69

Hey Ryan!

 

After removing the set of twins the rear turbo is missing the hole exhaust wheel! LOL I was comparing them to a few other sets I have and there all different. So were just going to order a single turbo kit off egay

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