Boost leak??

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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Pntaste4evr99
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Posts: 341
Joined: Thu Mar 26, 2015 4:12 am
Location: Lake Stevens WA

Boost leak??

Post by Pntaste4evr99 »

Hey guys, I'm a noob to this forum, so please be patient. I've just done a 20g swap with a 550 rob tune and a 20g Ecu, the whole thing. And it seems that I have a boost leak since it won't spool up past 14-15psi before it starts hesitate and buck, and once or twice now backfire. I turned the boost down to about 12 now, runs good but still every once and awhile will still hesitate and back fire. No CEL no nothing. Just changed plugs today with one step colder NGKs. I've already presure checked the whole system(FMIC) and held to mid 20s psi without so much as a hiss or leak. So I'm kinda stuck...
My buddy says it could be the factory BPV or waste gate actuator. He has the same set up with his wagon, and hits 18psi all day long.


Is there any other things I could check??
Btw I have no AFR gauge installed, but have clean yellow tops, and walbro pump, so I THINK it's not a fuel prob....but I don't know....... Frustration is starting to take over.

Any help or direction would be awesome, thanks.
94 Winestone SS 5MT Rob 550 20g. (Pickle)
Original WA car with 460k miles and climbing
Legacy777
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Re: Boost leak??

Post by Legacy777 »

I would recommend getting an AFR gauge to help diagnose things. If your intake held pressure during a pressure test it should be ok and you shouldn't have a boost leak. I would not recommend running colder plugs unless you are finding that the regular plugs are having issues and the electrodes are wearing prematurely.

Hopefully others have some additional feedback. There are some folks in your area that may be able to help if they are available.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
mike-tracy
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Re: Boost leak??

Post by mike-tracy »

Try the standard recommended plugs and gap them down a bit.

edit:
http://bbs.legacycentral.org/viewtopic.php?f=2&t=48133
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
Pntaste4evr99
Winestone Cowboy
Posts: 341
Joined: Thu Mar 26, 2015 4:12 am
Location: Lake Stevens WA

Re: Boost leak??

Post by Pntaste4evr99 »

Wow! Thanks for that link, I would have never guessed it was the gaps. I'll put some new ones in a see if it fixes it, thanks again!!
94 Winestone SS 5MT Rob 550 20g. (Pickle)
Original WA car with 460k miles and climbing
Pntaste4evr99
Winestone Cowboy
Posts: 341
Joined: Thu Mar 26, 2015 4:12 am
Location: Lake Stevens WA

Re: Boost leak??

Post by Pntaste4evr99 »

Wanted to say thanks Mike-Tracy the plugs seamed to do the trick. It would have took me a long time to figure that out, thanks again!!
94 Winestone SS 5MT Rob 550 20g. (Pickle)
Original WA car with 460k miles and climbing
mike-tracy
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Joined: Tue Aug 25, 2009 7:52 am
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Re: Boost leak??

Post by mike-tracy »

Glad that's what it was!
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
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