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Old 03-13-2013, 12:20 AM   #1
Luc r
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Default wastegate hose missing? (pics)

was looking at my puny td04 today and noticed that it looks like theres a hose missing off of the wastegate? i have a MBC thats hooked up to the turbo, but does there need to be a hose where my finger points? and where does it hook up to?
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Old 03-13-2013, 12:36 AM   #2
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That is the wastegate actuator and needs a boost reference hose. Unless you have an EWG?
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Old 03-13-2013, 12:37 AM   #3
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Quote:
Originally Posted by vision.dynamix View Post
That is the wastegate actuator and needs a boost reference hose. Unless you have an EWG?
its all stock, so im pretty sure its IWG?
where does the other end of the hose go to?
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Old 03-13-2013, 12:39 AM   #4
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Your car looks like a cluster****. Bring it to a tuner to have them look it over and spend a couple hours tying up loose ends.
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Old 03-13-2013, 12:44 AM   #5
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so other than it looks like a cluster****...thats helpfull and all, but where does the hose go to from the actuator so i can put a new one on
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Old 03-13-2013, 12:48 AM   #6
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Turbo outlet nipple goes to the inlet of the MBC.
Outlet of the MBC goes to the WG nipple.

If you have a MBC your car is not all stock.
Are you using engine management? What did boost look like with the MBC not connected? How long has it been like this? I could on but I will just stop here.
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Old 03-13-2013, 01:02 AM   #7
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That orange FMIC pipe is not stock.
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Old 03-13-2013, 01:12 AM   #8
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Only thing stock is like I said earlier...the turbo...
Yes, street tune 2 months ago after I added everything by my tuner. Not going into details on everything on the car. Just needed to know where house attached to.
Thanks jebjkey!
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Old 03-13-2013, 01:17 AM   #9
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Put a zip tie on there to keep it from coming off again.
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Old 03-13-2013, 05:41 AM   #10
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Out of curiosity, can I see a picture of your engine bay?
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Old 03-13-2013, 08:26 AM   #11
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Quote:
Originally Posted by vision.dynamix View Post
That is the wastegate actuator and needs a boost reference hose. Unless you have an EWG?
That'd be silly to have an EWG if he didn't use a bracket to keep the IWG closed

OP, why are you using a MBC? If you were using it along with an EBCS, that'd be cool... but just a MBC? I hope you know the dangers of that.
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Old 03-13-2013, 08:31 AM   #12
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Quote:
Originally Posted by Mr Wrex View Post
That'd be silly to have an EWG if he didn't use a bracket to keep the IWG closed

OP, why are you using a MBC? If you were using it along with an EBCS, that'd be cool... but just a MBC? I hope you know the dangers of that.
I ran an EWG with the IWG in place. My bracket was a simple piece of metal, 1x2", bent in the middle at ~30*, with a hole on one side for the downpipe bolt. Worked great. Im able to swap between IWG and EWG in the time it takes to flash a map.
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Old 03-13-2013, 11:33 AM   #13
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Quote:
Originally Posted by Mr Wrex View Post
That'd be silly to have an EWG if he didn't use a bracket to keep the IWG closed

OP, why are you using a MBC? If you were using it along with an EBCS, that'd be cool... but just a MBC? I hope you know the dangers of that.
bought the car 8 months ago and the MBC was on it. do not have an EBCS
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Old 03-13-2013, 12:59 PM   #14
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[quote=... but just a MBC? I hope you know the dangers of that.[/QUOTE]

What dangers exactly? Partial throttle full boost on a td04? Thats not going to hurt anything.

With that line disconnected, there is no pressure on the wastegate actuator so the wastegate will always stay closed. Basically you are trying to make as much boost as you can all the time. On the other hand, if you ran a line directly to the nipple on the outlet of the turbo you would be running the wastegate spring pressure. The MBC vents some pressure, so the actuator sees less pressure, thus you can adjust the boost pressure to any value between the spring pressure and the maximum pressure the turbo can put out.
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Old 03-13-2013, 01:01 PM   #15
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Originally Posted by CarverHouseRally View Post
Basically you are trying to make as much boost as you can all the time.
Except the TD04 IWG gets blown open with a sneeze.
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Old 03-13-2013, 02:59 PM   #16
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Quote:
Originally Posted by CarverHouseRally View Post
What dangers exactly? Partial throttle full boost on a td04? Thats not going to hurt anything.

With that line disconnected, there is no pressure on the wastegate actuator so the wastegate will always stay closed. Basically you are trying to make as much boost as you can all the time. On the other hand, if you ran a line directly to the nipple on the outlet of the turbo you would be running the wastegate spring pressure. The MBC vents some pressure, so the actuator sees less pressure, thus you can adjust the boost pressure to any value between the spring pressure and the maximum pressure the turbo can put out.
Plenty of them... biggest one is that the ECU cannot be used as a failsafe should the MBC malfunction. Also, boost spike, the lack of boost taper, and possible lean AFRs at partial throttle. The only way to safely run one is to have both an EGT and Boost gauge to monitor everything while you're driving, but I'd still avoid it unless you want a new motor.
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Old 03-13-2013, 05:17 PM   #17
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Quote:
Originally Posted by Mr Wrex View Post
Plenty of them... biggest one is that the ECU cannot be used as a failsafe should the MBC malfunction. Also, boost spike, the lack of boost taper, and possible lean AFRs at partial throttle. The only way to safely run one is to have both an EGT and Boost gauge to monitor everything while you're driving, but I'd still avoid it unless you want a new motor.
It will still cut fuel and pull timing if it overboosts, just like if the ebcs failed. Why would it lean out? Fueling is based on load (g/rev) and rpm, it doesn't care what the throttle position is.
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Old 03-13-2013, 05:17 PM   #18
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PTFB is bad on any turbo.
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Old 03-13-2013, 05:21 PM   #19
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Nope.
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Old 03-14-2013, 01:16 PM   #20
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I think PTFB concerns are a carry over from old MAP based (SD) cars. It is a problem for them, but it is not a problem for MAF based cars.

The turbo does not know or care where the throttle is on your car. Full throttle on one car might only be half throttle on another car (as far as the amount of air flow goes).

Boost spike is not a problem with any good MBC.
Trust me, boost tapers just the same on a MBC VF39 as it does on a EBCS VF39.
AFR has nothing to do with throttle position, only load and RPM. If you go lean at partial throttle, then your tune is at fault, not the MBC.

The new trend is HBC (hybrid boost control). It uses a MBC and an EBCS together.
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Old 03-14-2013, 02:35 PM   #21
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Quote:
Originally Posted by jebjkey View Post
I think PTFB concerns are a carry over from old MAP based (SD) cars. It is a problem for them, but it is not a problem for MAF based cars.

The turbo does not know or care where the throttle is on your car. Full throttle on one car might only be half throttle on another car (as far as the amount of air flow goes).

Boost spike is not a problem with any good MBC.
Trust me, boost tapers just the same on a MBC VF39 as it does on a EBCS VF39.
AFR has nothing to do with throttle position, only load and RPM. If you go lean at partial throttle, then your tune is at fault, not the MBC.

The new trend is HBC (hybrid boost control). It uses a MBC and an EBCS together.
I'm well aware of PFTB and it's still a problem on MAF based systems, but I have read you're able to tune around that. As to how, I haven't the slightest clue how they would trigger more fueling, but I'm sure someone has figured it out since 2004... MBCs are really just like playing with fire at times though; PFTB with lean AFRs will kill engines in no time. Also, imagine driving around in the snow trying to putt around and having full boost even at PFTB. Wouldn't that be a bizotch...

Without an EBCS, what's going to tell the ECU to taper the boost? The only thing that would control taper is a turbo reaching its flow capacity. What happens when your MBC decides to fail and you don't have any gauges to monitor your car? Hybrid is definitely a better option than just a MBC... I'd never want to give up the failsafe that the EBCS provides.

Last edited by Mr Wrex; 03-14-2013 at 02:49 PM.
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Old 03-14-2013, 09:32 PM   #22
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Once again, fueling is completely derived from current RPM and load. Load is MAF/RPM*60. There is no throttle input there. The engine gets the correct amount of fuel because it comes from the MAF reading.

If you are only 25% throttle but the turbo is pumping out 25# boost, your MAF reading will still tell the ECU exactly how much air is coming into the engine.

Say you are flowing 250 g/sec of air at 4500RPM, so your load is 3.33g/rev. The ECU will will look up 3.33 load at 4500RPM and inject enough fuel for whatever AFR is called out in the table. Where in that sequence did the ECU even care where the throttle was?

The only posibility is if your ECU holds on to closed loop fueling as load goes up. It should not do this unless you (or your tuner) changed a map table for the worse to make it hold closed loop too long.

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