Boost Leak Problems

[Switchback]

So, I've got a boost leak. At least, that's what Jason at Dizzy is telling me. I'm sitting at a max boost of 20PSI, and I've checked every boost connection on the vehicle without any luck, and I'm out of ideas. Jason told me that his tune should max out at around 26psi (+/- 1psi) I even purchased a new Symposer delete as the one I had was a bit finicky and I wanted to rule that out. I have a track day at the end of march and I don't feel like driving the Fiesta while it's maxing out at ~177HP is going to be good or fun. Anyone have any ideas what it might be? The car has 121k miles, could it be a turbo failing?

If I can't get this solved, should I just flip it back to the Cobb stage 2 tune? I think the Cobb Stage 2 tune maxes out at 21PSI so I might have a bit more performance while trying to figure out what in blazes is going wrong...

 

[sczamun]

Are you running a stock BPV?

 

[Switchback]

Are you running a stock BPV?

Yeah I am, will it not let me go over 20psi?

 

[Grsemky]

Yeah I am, will it not let me go over 20psi?

The diverter can just be getting weak, highly recommend the GFB diverter+

 

[Switchback]

Pardon my ignorance but what’s the difference between a diverter valve and something like the turbo smart bov? I’m thinking of going hybrid turbo in the future and the cost difference between the diverter+ and the turbosmart 14psi is negligible. If they install in the same place would replacing the stock diverter with either possibly fix the problem?

 

[dhminer]

Pardon my ignorance but what’s the difference between a diverter valve and something like the turbo smart bov? I’m thinking of going hybrid turbo in the future and the cost difference between the diverter+ and the turbosmart 14psi is negligible. If they install in the same place would replacing the stock diverter with either possibly fix the problem?

Matter of preference but I would go for the turbosmart. Electrical or mechanical actuation doesn’t matter much, also a matter of preference. I prefer mechanical BOV/BPV. Keep in mind you need to make periodically service an aftermarket unit and that’s a huge pain on the turbo which is why many block off the turbo port and put a VTA blow off on the symposer port.

BPV is a common source of boost leak. I’m sure you have already gone through and checked all your hose clamps between the turbo and throttle body and inspected the intercooler for cracks so the BPV is a logical next place to look. Your turbo may be tired as well.

 

[Grsemky]

Pardon my ignorance but what’s the difference between a diverter valve and something like the turbo smart bov? I’m thinking of going hybrid turbo in the future and the cost difference between the diverter+ and the turbosmart 14psi is negligible. If they install in the same place would replacing the stock diverter with either possibly fix the problem?

Diverter serves the same purpose as a BOV, and is how the factory boost pressure is handled on throttle close. A diverter recirculates the boost into the intake system whereas a BOV releases that into the atmosphere for that pssh pssh...

Now you mentioned turbosmart 14psi, and that would be in reference to the waste gate actuator. The waste gate controls boost pressure at the turbine by bypassing the turbine via a door. The actuator has spring pressure which relates to the minimum boost it will allow a turbo to produce. So a 14psi waste gate actuator will not allow you to make less than 14psi, factory is like 5psi...

 

[XanRules]

IF you have indeed THOROUGHLY checked every single vacuum connection, I believe I had the same issue when I got my tune and it was also the diverter valve. I would also agree on the GFB - I will always prefer a mechanical piece like that rather than electronic or digital but this is entirely personal preference. Check with Jason before you do this as he may have preferences on which one you should buy.

 

[Switchback]

Okay I’m getting the WGA and a BOV confused, my bad. I definitely prefer a WGA as I live in Cali and don’t want to give the cops extra reason to pull me over.
I’ll check with Jason, see what he thinks re brands.

As for checking for leaks, I was hunting down every line I could think of and checked everything that I could. Couldn’t find anything. Since I’m getting close to the track day deadline I may just take the Fiesta to the shop and have them figure it out.

 

[Grsemky]

I definitely prefer a WGA as I live in Cali and don’t want to give the cops extra reason to pull me over.
I’ll check with Jason, see what he thinks re brands

GFB diverter+ doesn't vent so you'll sound stock and even uses the factory solenoid

Also they perform two different functions and you need both... Just not necessarily upgrade both

 

[dhminer]

Yeah, don’t touch the wastegate actuator. Unless it’s totally cooked, which is unlikely, there’s not a substantial benefit of swapping it on the stock turbo. BPV, BOV, and diverter are interchangeable in terms of function. Just pick which you like the design and function of. They all hold boost better than stock

 

[Switchback]

Thanks, I’ll probably go with the DV+. Hopefully if I order today it will arrive before next Friday.
On the question of DV+ valves, should I get $240 one or the $150 one? I’m assuming the $240 needs less assembly and the $150 requires some donor parts from the original?

Also I’ve read I need to reset the ECU for relearning, is that accurate or not really?

 

[Grsemky]

Thanks, I’ll probably go with the DV+. Hopefully if I order today it will arrive before next Friday.
On the question of DV+ valves, should I get $240 one or the $150 one? I’m assuming the $240 needs less assembly and the $150 requires some donor parts from the original?

Also I’ve read I need to reset the ECU for relearning, is that accurate or not really?

I did not have the ECU reset or anything tuning wise, it functions identically to stock just with an improved design... The $240 one comes with a brand new solenoid which is just a copper coil in a plastic shroud, really no need to replace unless it's actually failed

 

[Switchback]

Gotcha, thanks! I ended up buying the newer valve version just because I’m not sure about the valve status but also the car is 11 years old and I didn’t want to run any risks.

As a backup I am preparing my Corvette for the track just in case I can’t get the Fiesta sorted out beforehand.

 

[Grsemky]

If you bought from whoosh you'll probably get it in like 1.5 weeks depending on location

 

[Switchback]

If you bought from whoosh you'll probably get it in like 1.5 weeks depending on location

You’re joking, right? I ordered and it’s already moved to shipping prep, UPS ground. I’m hopeful, don’t make me sad like that lol. But again, worst case I can run the Cobb stage 2 tune or just drive the corvette.

 

[Grsemky]

You’re joking, right? I ordered and it’s already moved to shipping prep, UPS ground. I’m hopeful, don’t make me sad like that lol. But again, worst case I can run the Cobb stage 2 tune or just drive the corvette.

Sometimes he doesn't have the stock and gets it shipped from GFB