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2017 Spider Abarth AT
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Discussion Starter · #1 ·
So here's one for the WG and Diverter Vale experts. I've been having issues with underboost, CELs and P0299 codes that I'm trying to run down. Other than the DV+ the turbo and associated plumbing is stock. Today, just for giggles, I swapped out my GFB DV+ for a stock unit I had lying around. Other than the mediocre performance that the stock DV provides, the car is now holding boost and no CELs yet, after some hard driving. I was a bit surprised, and a visual once-over of the GFB part didn't show any obvious issue. The DV+ is probably four years old and had been working fine. The only thing I haven't done since installation, is to re-lubricate the piston. I assumed that the initial application of oil combined with what it would pick up in ordinary use would have kept the piston adequately lubed. Is it possible that the piston simply got stuck? Anyone else have issues with the DV+. I'm hesitant to reinstall it without knowing for certain whether it was the cause of the problems I've been having. Anyone else encounter problems with the DV+ that would cause the engine not to hold any boost at all? Thanks.
 

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I replaced my stock dv for the gfb one and only noticed a hole in my bank account.
No performance difference at all with my non track spirited driving.
So you're saying your stock one is rubbish, and the dv+ is also, apparently rubbish.
Bit of bad luck I'd say.
Perhaps other issues are at play? Or you could reinstall following all instructions as if you hadn't read them before and see how it goes?
 

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2018 Nero Cinema Abarth 6MT
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After installing mine, I noticed a difference more in “casual” driving. When just driving around and not being aggressive in the true power band, I felt less lag compared to the stock DV, which when I first was driving the car, was noticeable when shifting, say around 3000rpm. But YMMV depending on how you drive I’d bet. It’s off the car now and the piston moves freely, etc. No issues.
 

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2017 Spider Abarth AT
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Discussion Starter · #5 ·
I can definitely feel a difference between the DV+ and the stock unit. With the DV+, boost felt “crisper” is the best way I can put it. The stock unit doesn’t seem to hold boost as well and the process of boost on and off just feels more vague. I haven’t quantified this objectively so everything I’m saying is based solely on ny experience driving the car with and without the DV+. I wouldn’t call either part rubbish…they are each built and perform differently. The DV+ worked fine for me for four years. The construction seems to be of higher quality than the Pierburg unit that Mopar used in the 1.4 multiair.

Since the DV+ is only a portion of the entire WG assembly, there is a possibility that the electrical connection to the solenoid on the dv is bad. I’m going to get a new DV+ and use it with the new solenoid portion of the dv. If that works, I may try to put the old DV+ on the new Mopar body just to confirm my theory. We’ll see.
 

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I went in pessimistic yet noticed a perceptible difference right away, so I wouldn't say it was placebo for me. It all depends on how bad your stocker valve was leaking. I remove my GFB DV for each oil change particular because it makes removing the oil filter cap easier and also so I can inspect the piston and gaskets and lube with fresh oil.
 

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I went in pessimistic yet noticed a perceptible difference right away, so I wouldn't say it was placebo for me. It all depends on how bad your stocker valve was leaking. I remove my GFB DV for each oil change particular because it makes removing the oil filter cap easier and also so I can inspect the piston and gaskets and lube with fresh oil.
As I understand it the issue with stock is not about a leak. Stock design works as intended. The stock DV is designed to vent instantly where the GFB DV holds boost on gear change so boost isn't lost and doesn't have to build again when you get back on the throttle.
 

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As I understand it the issue with stock is not about a leak. Stock design works as intended. The stock DV is designed to vent instantly where the GFB DV holds boost on gear change so boost isn't lost and doesn't have to build again when you get back on the throttle.
I suppose that's what I meant by "leaking". The GFB DV for me noticeably held pressure.
 

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I have had the same problem. Boost leak turned out to be the GFB DV+ valve. It didn’t close all the way. Took it out. Cleaned and polished it. Drip of oil. No problem since.
 

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Discussion Starter · #10 ·
I have had the same problem. Boost leak turned out to be the GFB DV+ valve. It didn’t close all the way. Took it out. Cleaned and polished it. Drip of oil. No problem since.
Thanks. I've got a new DV+ on order, mostly because I don't like the way the car responds with the stock unit. After four years there's probably also a bit of wear on the piston. Since it's manufactured to a very close tolerance, any deviations could cause it to stick. Also my not relubing it in four years may have had something to do with it. I'll see how it works when the new DV+ shows up...which should be in a couple of days.
 

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Fiat 124 Spider w/ Abarth LSD & RM
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Just a wossshhh modification... and the noise confuses a lot!

There is a big difference between a car with and without DV... an dv upgrade will bring no noticeable changes, for sure!

Stock hold the pressure fine and keeps the turbo rotating when you change the gear.

With the car remapped the car will have more boost and the stock DV will leak soon, just that...
 
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