mrbadger Posted July 29, 2007 Share Posted July 29, 2007 Boost readings at idle -210mmHg and reasonably static +-1mmHg. I'm led to believe that this should be fluctuating around about the -400 or -500 mark! The hoses have all been checked over as best I can visually and I took the hoses off and finger over one end blew down them as hard as I could. I was told when mapping the car that this was likely to be an electronic sensor fault as the reading is never usually that static. I got a new boost sensor (Thanks Peter) and it still hasn't fixed it. It's very frustrating as I can't run my top map of 1.2bar because apparently it is clipping at the higher end - probably due to the same problem. I'm currently running 1.15bar map. The car is MY98 Classic. All hoses above checked. I took off all the pipes around the boost sensor and checked they were ok visually, for blockages and leaks. I got a bit mixed up with a directional valve going to some sort of filter when doing this (please see other post). When I take the blue indicated pipe off the directional valve, I get a very good vacuum and the boost reading goes all over the place. I can't remember if I get a -500 reading if I put my finger over the vacuum or if I leave it open - one or the other I think? Could this be a clue? Help! Where is the mighty Squirrel! Any clues anyone? Link to comment
ally-b Posted July 29, 2007 Share Posted July 29, 2007 Poor Squiggle will be 'spent' after the Time-attack at K-H today []. He was spotted twitching uncontrollably (in a rather provocative manner [^o)]), as the Roger Clark Scoob glided round the hairpin . - and his behaviour when he saw his heros dad (Jimmy MacRae) was simply not suitable for this forum [] . . .I'm sure he'll be able to advise you Duncan [] Al. Link to comment
mrbadger Posted July 29, 2007 Author Share Posted July 29, 2007 Lol. I'll get the valium to calm him down a bit. Sounds like it was a fantastic day. Sad I missed it. Link to comment
brian_paterson Posted July 29, 2007 Share Posted July 29, 2007 The filter thing is for fuel vapour, i keep meaning to join the two hoses from the left bung the other pipe and throw this in the bin!!!!!!! the two pipes that get connected are the ones on the left as you look at it, the one with direction arrow on it, bung the other pipe and chuck black can in bin job done. Bri Link to comment
mrbadger Posted July 29, 2007 Author Share Posted July 29, 2007 Which direction should the arrow be pointing? When you say bung- do you mean throw away or block up? Still a bit confused..... Help! Will that be effecting the boost at idle? Link to comment
brian_paterson Posted July 29, 2007 Share Posted July 29, 2007 The arrow is to face back the way, bung the third pipe join the other two as you look at them from the front of the car. This is a fuel vapour filter and shouldn't be affecting your boost anyway? I would take it join the two pipes one in middle with the arrow thingy on it and push it into the pipe on the left bung the pipe on the right thfow black can in the bin and see if she runs any better. Bri Link to comment
brian_paterson Posted July 29, 2007 Share Posted July 29, 2007 sorry bung as in block Link to comment
the squiggle Posted July 29, 2007 Share Posted July 29, 2007 Which direction should the arrow be pointing? When you say bung- do you mean throw away or block up? Still a bit confused..... Help! Will that be effecting the boost at idle? Sounds like an air leak at idle The filter you are showing is a Carbon cannister, it traps fuel vapour Not sure about the UK98 as i have a JDM 96, mine has only 2 coming off the Carbon Cannister and i am not sure where the 3rd one goes but it sounds like a hose is split between the manifold and the Cannister. A split pipe coming off the manifold to show less of a depression reading on the Commander if it after the throttle body. At idle it should read in the region of -550hg so your -200 odd is showing air is getting into the manifold area through somewhere and more than likely it will be via a split pipe Link to comment
mrbadger Posted July 29, 2007 Author Share Posted July 29, 2007 I had a look last night, and took all the hoses off and inspected them. I may have missed something or may have a leaky join somewhere so I'll check again. Thanks Squirrel my fluffy animal friend Link to comment
the squiggle Posted July 29, 2007 Share Posted July 29, 2007 The pipes Subaru use are very brittle. They may look fine but you really need to put them under vacuum conditions to check them properly. The drop of 300hg says to me that it is quite a large split somewhere Link to comment
mrbadger Posted July 30, 2007 Author Share Posted July 30, 2007 Ok, I checked again and still can't see anything. I did notice that if I pulled off the hose going to the directional valve near the fuel vapour cannister - I got a strong vacuum and if I put my finger over the hose I got about -485. Is this a clue? Excuse the crude diagram:- Link to comment
the squiggle Posted July 30, 2007 Share Posted July 30, 2007 Ok, I checked again and still can't see anything. I did notice that if I pulled off the hose going to the directional valve near the fuel vapour cannister - I got a strong vacuum and if I put my finger over the hose I got about -485. Is this a clue? Excuse the crude diagram:- Far from crude sir On the right ines, -480hg is in the ball park for what is needed That means the pipework between where your finger was and the manifold is gas tight. So the problem lies between the MAF and the Directional valve/Carbon Cannister Link to comment
mrbadger Posted July 30, 2007 Author Share Posted July 30, 2007 Could it be the directional valve is faulty/leaking? Why does the vacuum go to the directional valve? Should I pull off the charcoal canister side and block it and also the MAF air instake side to see what happens to the vacuum reading? Sorry for being a technical numbskull. I really appreciate the help! Link to comment
the squiggle Posted July 31, 2007 Share Posted July 31, 2007 Yes block them off for the moment. It is possible for the Directional valve to be leaking I really need a look at a MY98 to remember how it feeds the air around that part of the engine, where are you from?. The Carbon Cannister is not crucial to the running of the engine and can be removed safely, the directional valve is there to stop you blowing positive boost down the hose and pressurising the fuel tank. Link to comment
brian_paterson Posted July 31, 2007 Share Posted July 31, 2007 You can take a look at mine if you want squirrel as mine is 2000 uk same as Mr badgers engine? Link to comment
the squiggle Posted August 1, 2007 Share Posted August 1, 2007 Mr Badger, I touch goats with my mobile number Bry, cheers mate i will keep that in mind if i need a look see Link to comment
mrbadger Posted August 1, 2007 Author Share Posted August 1, 2007 Thankyou Squirrel & Bry. It really is a pleasure being part of this community when people like yourselves take time to help others. I have pm'd ya Squirel. Link to comment
mrbadger Posted August 7, 2007 Author Share Posted August 7, 2007 I got my problem sorted with many thanks to those who helped and got involved. The air leak was somewhere between the directional valve and the charcoal cannister (most likely the valve itself). The vacuum hose is disconnected from the one way valve and blocked for the moment. I'm getting around -475mmHg reading on idle - going higher on over-run. I'll get a replacement valve sometime soon if I can find a donor car. Just to put this finally to bed if anyone is searching and has the same problem. Link to comment
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