paulpicard Posted October 13, 2009 Share Posted October 13, 2009 Well, it's getting cold up here, and my '92 Loyale is reacting with the intermittent poor cold start symptoms again. I did the IAC service as suggested at this site last fall, and it worked fine all last winter, in fact, all summer as well. But now it's acting up again - just like a bad automatic choke. So my questions are: Do I clean and lube again? Or is it time to replace parts, and if so, what's available out there without going to the stealership? (BTW, the old wagon is about to turn 300,000 klicks so I'm still impressed with Subaru engineering!) :-\ Quote Link to comment Share on other sites More sharing options...
torxxx Posted October 13, 2009 Share Posted October 13, 2009 I'm sure the dealer could get ahold of a new IAC, but I'd cry when I saw the price. I've always cleaned them out with brake clean and they seemed to work fine after that. You could always goto a junkyard and find a low mileage car and snag one off it. Your engine would have to be running pretty poorly and have tons of oil blowing by the crankcase lines to actually mess up a IAC. I'd get a test schematic on the IAC (out of a FSM or chiltons) and follow it and make sure you arent having an electrical failure to it. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 13, 2009 Share Posted October 13, 2009 Yeah - best to get a good used one if you suspect it's not going to work to clean it this time. GD Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 13, 2009 Author Share Posted October 13, 2009 Thanks guys. I'm sort of leaning towards an intermittent electrical connection. The engine does use some oil, maybe a liter in 1500 klicks or so, but there is no gunk or blowby at the IAC location. I guess I'll just follow the wires and check ground connections, etc. Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 16, 2009 Author Share Posted October 16, 2009 OK, today, I removed the IAC unit, cleaned the valve body portion with brake cleaner, and cleaned the electrical connectors for it plus the temp. sensor. Upon re-assembly, the Soob started up and ran "by the book" Of course, the weather today didn't cooperate - it warmed up to 18C. So we'll see what happens when real weather returns! I did find oily residue in the PVC hoses though, but since I have never been able to figure out Subaru's PVC system, I haven't serviced that item. Should I? And if so, what's involved? (On my old V-8 Dodges and Chevs it's simply a check valve in the rocker cover, but it seems to be much more complicated in the Soob) Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 16, 2009 Share Posted October 16, 2009 The PCV is designed for positive flow of filtered air into the passenger side valve cover, through the crankcase, out the driver's side valve cover, and into the manifold to be burned. The check valve is attached to the back of the manifold. Additionally, due to the nature of the boxer design, there is a vacuum breaker line of smaller diameter inserted between the driver's side valve cover and the PCV valve itself to prevent the system from sucking oil out of the driver's side valve cover. This is about a 1/4" ID line. All these lines as well as the plastic connectors in the system get clogged up with oil and carbon and should be cleaned once in a while (probably something on the order of every timing belt change). Note that all the air that enters the engine - for the PCV as well - is metered by the MAF. As such you don't want to make changes to the PCV system as you might inadvertantly create a vacuum leak. Even pulling out the dipstick effectively creates a vacuum leak on SPFI cars because the air inside the crankcase is metered. GD Quote Link to comment Share on other sites More sharing options...
The Dude Abides Posted October 16, 2009 Share Posted October 16, 2009 I really need to do this as well. clean my iac and make sure my hoses arent clogged. Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 16, 2009 Author Share Posted October 16, 2009 GD, thanks - now I understand the reason for all that plumbing, and I'll clean it out as suggested. Is the check valve itself serviceable, or is it considered a "consumable" part like V-8 PCVs? Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 16, 2009 Author Share Posted October 16, 2009 GD, thanks - now I understand the reason for all that plumbing, and I'll clean it out as suggested. Is the check valve itself serviceable, or is it considered a "consumable" part like V-8 PCVs? GD, never mind - I have a new PCV arriving tomorrow, and I'll clean out the hoses and other bits then. Dude, the car started and idled "by the book" this AM, weather cool and raining. Clean those parts up!! Quote Link to comment Share on other sites More sharing options...
The Dude Abides Posted October 16, 2009 Share Posted October 16, 2009 The thing is, that the ps resevour is in the way. I know there are ways around this but it needs taken off anyways. The o ring is bad somewhere. Does anyone know what size o ring it takes on the bottom or side, or whever the darn thing leakes. But yes this and the cts sensor need cleaned up as well. Ben Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 17, 2009 Author Share Posted October 17, 2009 The thing is, that the ps resevour is in the way. I know there are ways around this but it needs taken off anyways. The o ring is bad somewhere. Does anyone know what size o ring it takes on the bottom or side, or whever the darn thing leakes. But yes this and the cts sensor need cleaned up as well. Ben Just take it off, measure the o-ring, and run over to your local parts store for a new one. Or better still, go find a pre-packaged assortment of o-rings, like I did, and you'll most likely have a candidate in the collection for whatever you need to do. Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 18, 2009 Author Share Posted October 18, 2009 GD, I did the PCV replacement today. I did not see any evidence of the "vacuum breaker" small i.d. line as you mentioned, connected to the main hoses. Can you give me more info on it's location? Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 23, 2009 Author Share Posted October 23, 2009 (edited) Update on "winter tuneup": While re & re-ing the PCV (screwed into the intake, not "pressed in" as Haynes says), I notced a plug wire literally fall off the dist. cap. Corroded all to hell. Plus rotor was worn at the tip. So, cap, rotor, and set of plug wires later, the car runs better. So much better at full throttle/4000 RPM+ I'm amazed. Before it would run up past 4000 but really didn't make that excercise worthwhile. Now the power continues to build up to 5000 - means I can now get past that loaded log truck without waiting for the 1 mile straight Am I just imagining this or would the cap/rotor/plug wire change have that much effect? Edited October 23, 2009 by paulpicard Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 23, 2009 Share Posted October 23, 2009 You may or may not have the PCV "fix" for long, sweeping, right hand turns causing clouds of oil smoke..... At any rate there should be a restriction somewhere on the line from the driver's side valve cover. Either the line will neck down to 1/4" ID, or there will be an oddball T fitting with an orifice drilled into it. On the carb models this is obvious as the line necks down with an "F" fitting going to the PCV and to the air-filter housing. With the SPFI's it looks different but the effect is similar. GD Quote Link to comment Share on other sites More sharing options...
eulogious Posted October 23, 2009 Share Posted October 23, 2009 You may or may not have the PCV "fix" for long, sweeping, right hand turns causing clouds of oil smoke..... GD, what causes this, or is it normal? I had this happen on my 87 carbed wagon back in the day, and it happened recently on my 90 turbo wagon and I was curious on why it happened only in long sweeping right hand turns... stupid Seattle area on-ramps :-\ Quote Link to comment Share on other sites More sharing options...
paulpicard Posted October 23, 2009 Author Share Posted October 23, 2009 At any rate there should be a restriction somewhere on the line from the driver's side valve cover. Either the line will neck down to 1/4" ID, or there will be an oddball T fitting with an orifice drilled into it. Negative on that, GD. Unless there's a restriction in the valve cover nipple itself. The hose is constant diameter one piece to the T for the PCV valve. And that T has no restrictions either. I couldn't tell you if the right-turn oil burning occurs (I'm a 100 miles from any on-ramps ) but the car does use some oil - no leaks or blue smoke visible. Suggestions? Like make a plug and drill it out to the appropriate size? Quote Link to comment Share on other sites More sharing options...
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