Jump to content
Ultimate Subaru Message Board

Auto suction Valve help


Recommended Posts

Hey everyone! I just got done installing free flowing exhaust on my 85 Brat, and now I am gettng the backfires. I did a search, and it seems that the auto suction valve can be a common problem. I heard someone mentioning the quarter trick, and I was wondering exactly what hoses I need to put the quarters in? I see the suction valve, and it had one small vac. line on top, then in the middle, there is a good sized hose that goes to some sort of a canister. Below that, there is a metal line that goes down to where the manifolds bolt up. So, I assume that I need to put a quarter in the middle hose, that goes to the canister. Is this correct? Also, do I neet to put a quarter in the hose that goes out of the canister? Thanks, Kurt

Link to comment
Share on other sites

You just need to block the pipe so air doesn't inject into the exhaust. Me, having the same problem... won't be doing this. I've read somewhere on the message board it will stuff you cat completly... i think it overheats and you'll lose power. So its only a temporary fix.

 

You can try pulling the Anti suction valve off, pulling it apart cleaning the reed valves and putting it back together. Or Shawn has this $10 fix for the problem... http://www.ultimatesubaru.org/forum/article.php?a=72 (if you do, can you grab two and post one to me, its a SOA part not available in Aus.)

 

If you leave it, the backfiring will melt the silencing which will go stuff the carb then stuff your valves. So the quarter trick will be better then leaving it backfiring...

Link to comment
Share on other sites

I assume you're getting backfires because there is no cat. I had the same problem when I gutted mine, and removing the ASV solved the problem. I plugged the hoses with bolts and that worked well.

 

If you do have a cat, then fix the valves.

Link to comment
Share on other sites

Yes, I "forgot" to replace the cat when I redid the exhaust. That makes perfect sense just to take the asv off, I dont know why I didnt think of that before! There are no emissions to pass here in Minnesota, so its no big deal. Thanks, Kurt

Link to comment
Share on other sites

I have cat-less exhaust too - When hubby and I plugged my ASV's off, we cut a piece of sheet metal to go between the stainless lines that lead to the ASV and the manifold (unbolted the lines, put in sheet metal 'plug' on manifold, then bolted the lines back up. This way everything is still there if we ever decide to put the exhaust with cats back on and want to fix the ASV's instead of disable them.....

Link to comment
Share on other sites

You can try pulling the Anti suction valve off, pulling it apart cleaning the reed valves and putting it back together.

 

I did this to mine and it's still noisey as hell.. the reed and ASV's are fine.. it's only noisy on the drivers side.. .any ideas? If you need more details of whats going on with mine.. http://www.ultimatesubaru.org/forum/showthread.php?t=34967&page=1&pp=10

Link to comment
Share on other sites

I did this to mine and it's still noisey as hell.. the reed and ASV's are fine.. it's only noisy on the drivers side.. .any ideas? If you need more details of whats going on with mine..
Probably the little black plastice thing sitting above it. It's the silencer, maybe its seen its last days. Try replacing it with a 2nd hand one that looks good if its not too expensive. Because its only a guess...
Link to comment
Share on other sites

Problem fixed! Okay, on my 85 BRAT there are two of them. On each there is a metal line that screws in to the valve. Just unscrew those, put a quarter in, and screw them back on! I found that on the drivers side, it was easier to just pull the whole valve and metal line off at once, then disconect it out of the car. If anyone ever need help on this, just drop me a pm and I'll do my best to go into more detail! It solved the problem, and it only cost $.50!:clap: Coming soon, pics of the finished ehxahust setup! Thanks, Kurt

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...