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Hey guys, from a technical perspective. you aren't describing cavitation as such. Cavtitation occurs when the pressure on the suction side of the pump drops too low (usually a negative value determined by the pump design) for the pumps given amount of lift. This boils the fluid on the suction side of the pump and the bubbles then collapse on the impeller. What you guys are describing is more like what I would refer to as dead-heading a pump. This is where the fluid essentially stalls (relative to the impeller) and you get fluid slip on the impeller (like compressor surge). It sounds like you are driving the pump off the end of its operational curve, and this is driving the current draw up and frying the pump motor. Can someone measure a dead pumps electrical resistance versus a good pump? Cavitation would destroy the impeller and maybe the shaft bearings/surfaces. Dead-heading will burn out the motor. Sent from my SM-G960F using Tapatalk

Making this topic so people wont run into the exact same issues @Niran and I experienced. Hopefully this will save people a lot of mucking around. The Problem The GV/GR fuel hanger seems to be a significantly restrictive part of the fuel system on late model STI's (MY08 - MY14). Because of this restriction it causes fuel pumps to get hot, cavitate, and eventually fail, causing big issues down the line. The part of the stock hanger which is returning fuel simply cannot flow enough fuel out of it to keep pace with the bypassed amount from regulator. What happens next is rather than the Return line being un-pressurized, it starts building pressure, which affects the performance of the regulator which in turn causes flow/pressure issues down the feed line, which then causes the fuel pump to cavitate. Cavitation link for reference if you don't know what it is. The Solution This issue can be resolved by using a surge tank setup, or by replacing the fuel hanger with an aftermarket alternative. Radium Engineering hangers have been proven to resolve the issue, as well as the Process West surge tank option. The reason why going to a surge tank solves this issue is because you also change from a high pressure fuel pump, to a low pressure high flow pump which just dumps into the Surge tank. Additional Info This may also apply to a select legacy GT's between MY05 and MY07. Someone to confirm, perhaps @Andy_Mac may know, but I believe they use the same hanger. Please note that this discussion is aimed more towards people chasing big power (300kw +) If you are doing simple bolt-on's this may not apply to you so don't worry! Solution A: Aftermarket Fuel Hanger The below is for a Radium Fuel Pump Hanger. (20-0380-00, 20-0382-00, 20-0383-00) It is recommended to purchase the plumbing kit for this too. Solution B: Surge Tank Process West Anti-Surge Fuel System - https://processwest.com.au/surgetank-08-14 Solution C: Hack Job Nobody we're aware of has tried this yet, if someone does can you take pictures and post up step by step instructions and ill add it in here. Contributors: @Dairusire @Andy_Mac

Could try that one with a custom return setup but it will be a lot of pissing around where the full radium hanger will do everything better and probably more reliably http://www.radiumauto.com/Venturi-Jet-Pump-Kit-P760.aspx

@pl0x mine munched about 3 fuel pumps. Didn't have as many issues on idle i don't think. Idle is actually a bit funky now with the surge tank setup. But not a biggie. I think the complexity about modifying the stock cradle is to do with not messing up the venturi that draws fuel from the other side of the tank. Not sure how you solve that when hacking away at it. If you have a solution for that, then hack it up and always keep the tank full - cheap fix

Hey Team, The age old issue with the Subaru cars 2007 models of the secondary air pump value being stuck open has hit my car. I will be blanking the secondary air pumps off this weekend and was wondering if some one could override the error codes. Thanks 👍

Can't think of who on here is in Hamilton. I can do it but I'm over in Tauranga

If you can drive to pukekohe you could get PBMS to do it for you

@Tony might be able to elaborate further. They had a cradle in storage at DTech which they had modified to flow better including adding a second return. Routing the return out of the cradle is what I've been thinking of doing. Just need to have a closer look at it to decide if there will be any negative outcomes from doing that.

What @Andy_Mac said is right, but to expand on it. To achieve 300KW+ you need a very high flowing high pressure Fuel pump, this goes up the feed line pressurised and through the rails to the regulator. Regulator then sends fuel back down the return line to tank. The part of the stock hanger which is returning fuel simply cannot flow enough fuel out of it to keep pace with the bypassed amount from regulator. What happens next is rather than the Return line being unpressurised, it starts building pressure, which affects the performance of the regulator which in turn causes flow/pressure issues down the feed line, which then causes the fuel pump to cavitate. https://en.wikipedia.org/wiki/Cavitation link for reference if you don't know what it is. So in short, you modify/replace/change the stock hanger so there is no restriction and thus no pressure issues which could solve your entire problem. The reason why going to a surge tank solves this issue is because you also change from a high pressure fuel pump, to a low pressure high flow pump which just dumps into the Surge tank. EDITS: Because I'm dyslexic, I'm fixing my grammar and spelling as I spot it. Have to re-read things like this 10,000 times to make sure I've got it all

You know as soon as I listened and watched that video I called it being spark plugs before I saw your solution. Why? I've done the same thing before haha.

Damn that is loud. Glad it's fixed though.

At an even higher level, like most things in life, mismanaged expectations and poor communication are the fundamentals to satisfaction in general. In my own experiences, I always clarify the price, or expected price range for a piece of work whether its planned or unplanned, for anything and everything. For a more relatable example, when my car was with Tony for the fuel system fitting and tune, my P/S pump started to leak. As expected, Tony called me, quoted me a price range to pull and diagnose the pump. Didn't promise me anything about the resolution or price of it but in the end diagnosis was a bad o-ring, so to replace it was a couple bucks more as the pump was already apart. Whilst the additional cost was unplanned, the management of the problem through to resolution met my expectations for a professional and experienced outfit. Furthermore, this was all detailed to a high degree on my invoice and reflected the phone and email conversations we'd had. In other examples, when outfits don't meet my expectations, I simply don't use them again. I vote with my wallet and that way I find outfits that do align with and agree to my expectations.