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Boost Leak Problems

sczamun

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#21
I just checked and it’s coming from Vegas and ETA is Monday, so he definitely has some in stock. It was a very quick turnaround between order and shipping so I wonder if he’s lurking the forums and associated this post with my account. Either way, that’s good.

I also spent the money on a pressure leak tester so I’m going to pressurize the system and see if there’s a leak. I’m going to fix this damned problem if it’s the last thing I do.
Back after my initial post on Thursday. I was running low on boost, about 1-2 psi before I got the same DIV+/solenoid. It also just seemed to work better overall, with boost consistently going into throttle as well.
 


OP
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Thread Starter #22
Okay, back from the track day (Took the Corvette) and an update. The DV+ did not fix the boost leak, and I tried to pressure test the system with a new boost leak test kit. The system wouldn't hold any pressure and would max out at 21PSI when applying 26PSI of pressure through the system. I couldn't keep it pressurized without adding air to the system, so something is definitely wrong. I also found what appears to be an oil leak in the turbo area so I think I may be looking at some sort of turbo problem. Frankly this is beyond my skillset now, the cheapo-fiesta is very quickly becoming the very-not-cheap fiesta. Oh and the slave is starting to go out as well so transmission has to drop as well.
 


dhminer

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#23
Okay, back from the track day (Took the Corvette) and an update. The DV+ did not fix the boost leak, and I tried to pressure test the system with a new boost leak test kit. The system wouldn't hold any pressure and would max out at 21PSI when applying 26PSI of pressure through the system. I couldn't keep it pressurized without adding air to the system, so something is definitely wrong. I also found what appears to be an oil leak in the turbo area so I think I may be looking at some sort of turbo problem. Frankly this is beyond my skillset now, the cheapo-fiesta is very quickly becoming the very-not-cheap fiesta. Oh and the slave is starting to go out as well so transmission has to drop as well.
How did you do the boost test? There are some spots that will leak boost that you have to plug in order to do it correctly. You connected the plug/compressor at the turbo inlet, or the compressor outlet/hot side charge pipe?
 


OP
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Thread Starter #24
How did you do the boost test? There are some spots that will leak boost that you have to plug in order to do it correctly. You connected the plug/compressor at the turbo inlet, or the compressor outlet/hot side charge pipe?
Neither, I used the symposer delete hole to pressurize it, but also tried straight intake tubing. Like I said, I'm out of my depth :)
 


dhminer

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#25
Neither, I used the symposer delete hole to pressurize it, but also tried straight intake tubing. Like I said, I'm out of my depth :)
I can walk you through it if you want. I’ve chased similar boost issues before and it was infuriating while I fumbled through how to properly test for leaks but eventually got it sorted.
 


OP
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Thread Starter #26
I can walk you through it if you want. I’ve chased similar boost issues before and it was infuriating while I fumbled through how to properly test for leaks but eventually got it sorted.
I'd certainly appreciate it, maybe if you have some time this sunday. I've got the Corvette in the garage currently and saturday we are working on the 24h of Lemons car. The Fiesta is limping along as my daily for this week.

One item of note, I flipped over to the Cobb Stage 2 tune and now I'm maxing out at 17-18lb of boost on a cool evening. The Cobb tune should max out at 21lb of boost, so I figured I'd be making a bit more power. I also found what looks to be a seeping oil problem coming from the turbo area, which leads me to believe the turbo might be getting ready to sepuku itself.
 


Grsemky

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#27
I'd certainly appreciate it, maybe if you have some time this sunday. I've got the Corvette in the garage currently and saturday we are working on the 24h of Lemons car. The Fiesta is limping along as my daily for this week.

One item of note, I flipped over to the Cobb Stage 2 tune and now I'm maxing out at 17-18lb of boost on a cool evening. The Cobb tune should max out at 21lb of boost, so I figured I'd be making a bit more power. I also found what looks to be a seeping oil problem coming from the turbo area, which leads me to believe the turbo might be getting ready to sepuku itself.
That's not necessarily a fault though as our cars use torque demand to control boost. If the air is dense enough and good fuel in the tank, the ECU may not ask for all the boost 🤷🏼‍♂️ what was your WGDC at the peak boost?
 


dhminer

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#28
I'd certainly appreciate it, maybe if you have some time this sunday. I've got the Corvette in the garage currently and saturday we are working on the 24h of Lemons car. The Fiesta is limping along as my daily for this week.

One item of note, I flipped over to the Cobb Stage 2 tune and now I'm maxing out at 17-18lb of boost on a cool evening. The Cobb tune should max out at 21lb of boost, so I figured I'd be making a bit more power. I also found what looks to be a seeping oil problem coming from the turbo area, which leads me to believe the turbo might be getting ready to sepuku itself.
Ah, not good. That could be the cause of your boost issue. Shoot me a PM and I’ll give you my cell number to help with the boost leak test.
 


sczamun

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#29
I'd certainly appreciate it, maybe if you have some time this sunday. I've got the Corvette in the garage currently and saturday we are working on the 24h of Lemons car. The Fiesta is limping along as my daily for this week.

One item of note, I flipped over to the Cobb Stage 2 tune and now I'm maxing out at 17-18lb of boost on a cool evening. The Cobb tune should max out at 21lb of boost, so I figured I'd be making a bit more power. I also found what looks to be a seeping oil problem coming from the turbo area, which leads me to believe the turbo might be getting ready to sepuku itself.
Unless you know exactly where it's coming from, the leak could be many things. Could be the valve cover gasket or just the turbo oil feed/return fittings.
 


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