bogging at low rpms then hitting boost hard. whats going on?

[sliverumble]

The other day my charge piping, where my top mount attaches to the throttle body slipped off. So I reattached it tightened the hose clamp and seemed sealed. Still kept bogging at low rpms then hit boost and shot. I thought resetting the ecu would fix the issue. It didnt and this time popped, almost like a backfire and the boost guage seemed to spike. Any idea what this could be? All the boost lines were connected and fine, im not sure whats going on.

-Grant

[Apex3]

Maybe you forgot to reconnect your MAF when you were doing something? Or some sort of vacuum leak somewhere, could have knocked something loose

[sliverumble]

i know the maf is connected, a vacuum leak is possible. ill have to look it over closer. Thanks for the advise

[tturnpaw]

When I had this issue, it was partially the boost solenoid and my bpv leaked very badly and would flutter.

[sliverumble]

that does make sense. my bpv isnt looking so good on the underneeth side. the boost solenoid is reddish orange and black and sits next to the passenger strut tower correct?

[tturnpaw]

Yup. I will say again any Subaru bpv is garbage. Buy an upgrade. Like a bosche unit. I replaced mine with a 7m supra one and it works great. Going to tial soon though.

[vrg3]

The 7MGTE Supra blowoff valve looks almost identical to the stock Legacy piece except its housing is steel and aluminum rather than plastic. It's actually not that great either though; they commonly fail. What happened with the few I've taken apart is that a rubber gasket inside becomes brittle with age and quits sealing. I've repaired some by replacing the gasket with RTV silicone though.

Grant, what do you mean when you say it popped? If the boost gauge spiked at the time maybe you did get experience backfire. Is your ignition system in good shape?

The part you're describing (reddish orange and black) is the pressure exchange solenoid. The boost control solenoid is actually underneath it.

[sliverumble]

yeah the boost guage spiked, and sounded like a pop under the hood, almost as if it was popping though my cone filter or something. im not 100% sure. Im pretty sure my ignition system is fine, ive had no issues with it. Haha yeah I realized what part the boost control solenoid was right after i posted that last reply.

Will a wrx bov plummed to bypass instead of vent to atmosphere work just fine as a bpv?

[vrg3]

It sounds like it did backfire, which is a problem with the ignition system. Our cars don't usually backfire just because the plugs are worn or something, but I would still replace the spark plugs and carefully examine the wires to see if they could use replacement.

[sliverumble]

i know the plugs are good because their decently new. the wires arent so ill have a look at them. It could backfire if its in need of a tune couldnt it?

[vrg3]

What do you mean by "a tune?"

[sliverumble]

I mean remapping the air/fuel ratio's and adjusting the boost levels to work optimaly. I figured out that my bypass valve was in fact bad so that solved my problem.