ClassicScoobyJay

My MY99 UK Classic has suffered with the clogged up Boost Solenoid / Overboot / Thrusting issue since I bought it over a year ago.

I have followed the sound advice from fellow ScoobyNetters regarding using brake cleaner on the Boost Solenoid and surrounding pipes, and this initially fixed it for a month or so.

Following the first occurrence I always ensured that my oil was never more than 3/4 full, as I understand oil resevoir overfilling to be the common cause of the issue.

Even so, the issue kept returning, and I kept cleaning (I've even had Subaru carry out the procedure at every service). Progressively the issue has got worse, to the point where cleaning had no real effect.

As my car is still under warranty, I complained to my local Subaru dealer and demanded they find a permanent fix. Their suggestion was to replace my Boost Solenoid.

Since then (about a month ago) - the car seems like a completely different animal. Much smoother acceleration under boost, the ability to floor it in any gear without it overboosting (I can now overtake with complete confidence!) etc. It just feels like it is all working as designed now.

I must admit I haven't taken my old solenoid to bits to check, so maybe it simply had a bit of dirt in there that wouldn't shift no matter how vigorously I (and Subaru) cleaned it.

But there is also the possibility that, as it is a moving part, it must be prone to wear & tear of some sort, and maybe it had actually gone 'faulty'.

I believe the replacement solenoid to be the same design as the old, so I'm ruling out Subaru having fixed a design fault with the replacement.


The reason for my post is simply to say to those Classic drivers who are suffering in silence with this issue, having tried the solenoid cleaning to no avail, there is hope! Get yourself a new Boost Solenoid and you may find you start loving your Scoob again.

Cheers,

Jay

scooby_matt

I'm pretty new to the Subaru scene, so what should i be looking our for if the solenoid is playing up?

scoobyboy

always said it doesn't work cleaning it out

yhe chod

how much? and whats the part no. mate
cheers

TonyBurns

iTrader: (3)

Had a similar problem on an MY00 classic, took the car to the dealer, they cleaned the boost solenoid, problem resolved looks like you had an unlucky boost solenoid

Tony

ClassicScoobyJay

If you find your Classic seems to be 'thrusting' when you really floor it, that's the tell-tale sign. If you can floor it and it accelerates hard, but smooth, that's fine. A boost gauge makes it much more obvious as you actually see the needle fluctuating back & forth.

It was replaced on warranty for me so I can't really help there mate sorry. The garage that did the work for me was Hunt & Keale in Park Royal. I'm sure if you rang them they'd be happy to fill you in.

Aye

I sincerely hope it doesn't, but if the problem creeps back for you - maybe this thread will help one day

Saint AAI

Mine is doing this and cleaning worked for abit, but its doing it again so I may have to get a new one. Gonna try replacing it with the one from my GReddy boost controller first though.

Kirsty_Scoobz

Hi guys thanks for that been having this issue for about 2 weeks now been told (as I'm a female) could just be a vacuum leak from removing pipes from intercooler etc but having replaced most pipes this issue still there so will give this ago. Got a 1997 classic where exactly is the boost solenoid and how do I go about cleaning it😊 thanks x

kevo10

boost solenoid is on the drivers side suspension turret. connect the 2 green connectors uder the dash and the solenoid will start clicking and fans run so the solenoid can be identified and cleaned or replaced as needed

baker_boy

So just bringing this thread back from the dead, that's what the search buttons for right. I'm also having issues. I currently can't drive mine atm. Just bought a 94 plate sti import wagon. when I collected it the previous owner (my sister) hasn't driven it for about 6-8months as they bought another car so I towed it home as the mots ran out. Have just replaced the battery was it was flat.
My question is. When your at stand still and Rev it should the boost build high enough to allow the dump valve to come in to effect? The boost gauge reading doesn't go above 0. It moves around when revving but won't go any higher, could that be a stuck solenoid/actuator?

bludgod

iTrader: (3)

boost reading 0 at idle is normal enough - you'd only make boost sitting still if you had an antilag system in place. If the solenoid is off you'll either make very little boost or way too much boost (and get fuel cut). But you would only know when you drive it!

baker_boy

Iv been looking around, other vids etc. And seen other Imprezas sit there blipping the throttle and you can noteably hear the turbo, when revving should you be able to see the actuator arm moving? I can't hear mine at all. Concerned there could be an issue.

bludgod

iTrader: (3)

the actuator arm won't start to move until positive pressure is created to push it. if your not making boost the arm isn't moving. 0psi at idle is quite normal, check how much boost you make whilst moving to be sure if all is working or not.

baker_boy

Ok I'll have to wait and see once I get it motd. Was just seeing if I can get anything needed done now before I get rolling. Thanks for the help anyway.