Boost Leak Problems

[sczamun]

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.

 

[Switchback]

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]

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?

 

[Switchback]

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]

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.

 

[Switchback]

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]

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]

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]

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.

 

[Switchback]

So after switching back to the Cobb Stage 2 the car feels way better on power delivery. I think it's still down from potential max (I saw it hit 19.8psi of boost on my commute to work) but overall it feels way better than the Dizzy Stage 2. I have an appointment at a shop to take a look and actually pressure test everything correctly, and also do a once-over of the fiesta before I try to make it to a track day. With socal temps being what they are I want a pro to look it over. I will do a datalog tonight to see what the WGDC is at, is that what the car is requesting boost-wise?

 

[Grsemky]

So after switching back to the Cobb Stage 2 the car feels way better on power delivery. I think it's still down from potential max (I saw it hit 19.8psi of boost on my commute to work) but overall it feels way better than the Dizzy Stage 2. I have an appointment at a shop to take a look and actually pressure test everything correctly, and also do a once-over of the fiesta before I try to make it to a track day. With socal temps being what they are I want a pro to look it over. I will do a datalog tonight to see what the WGDC is at, is that what the car is requesting boost-wise?

Yeah the waste gate controls exhaust flow across the turbine, the higher the number the closer the gate is to diverting all exhaust through the turbine increasing boost... In Arizona on a dizzy stage 2 I'll see 24lbs at 80% duty in warmer weather. With the cooler air I see around 20lbs of boost... Though our gas sucks like Cali and the OAR will drop😭😭

 

[Switchback]

Yeah the waste gate controls exhaust flow across the turbine, the higher the number the closer the gate is to diverting all exhaust through the turbine increasing boost... In Arizona on a dizzy stage 2 I'll see 24lbs at 80% duty in warmer weather. With the cooler air I see around 20lbs of boost... Though our gas sucks like Cali and the OAR will drop😭😭

Just makes me feel like there's a notable issue with my car, either WG or turbo itself struggling. If the turbo is indeed going I guess it's time to consider a S280 or Whoosh Hybrid. Which I'd love an S280 as it seems to be the safer alternative for track use, but with California and state ref and smog nonsense I may have to go hide with a Whoosh hybrid.

 

[Switchback]

Yeah the waste gate controls exhaust flow across the turbine, the higher the number the closer the gate is to diverting all exhaust through the turbine increasing boost... In Arizona on a dizzy stage 2 I'll see 24lbs at 80% duty in warmer weather. With the cooler air I see around 20lbs of boost... Though our gas sucks like Cali and the OAR will drop😭😭

Finally did another datalog. When I put it into vdyno it does not look good, and looking at the datalogs while I'm no expert it certainly sees like it's not getting all the boost it should. Keep in mind both these runs were in pretty low evening ambient temps (60 degrees)


Something is certainly afoot. (the datalogs are csvs, just renamed to .txt so the forum doesn't spit it out at me) Datalog5 is my Dizzy stage 2, datalog8 is the Cobb stage 2 91oct tune. It's interesting how the Cobb Stage 2 has more power, but the Dizzy makes more boost.

 

[Switchback]

The saga continues, shop I was going to have look at it seems like they don't want the work (or would rather sit on the car for 2 weeks after a 4 week wait for an appointment), so now I'm back to square one. Could a failing evap purge valve cause this boost leak? I know the car stutters sometimes after a fuel fillup, but as long as the car isn't idling its fine...

 

[sczamun]

The saga continues, shop I was going to have look at it seems like they don't want the work (or would rather sit on the car for 2 weeks after a 4 week wait for an appointment), so now I'm back to square one. Could a failing evap purge valve cause this boost leak? I know the car stutters sometimes after a fuel fillup, but as long as the car isn't idling its fine...

I'd probably figure out what the oil leak is first, then the evap before the boost leak. But another common issue I've come across is the boost control solenoid. They are fragile and the little barbs for the hoses crack. I think the solenoid also gets weak over time. Might be worth checking.