bheinen74 Posted January 19, 2012 Share Posted January 19, 2012 again, timing. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 20, 2012 Author Share Posted January 20, 2012 "again, timing" Not sure what that means. I replaced the valve cover gaskets and plugs today. Not because of this problem, but to stop oil leak dripping its way back to get on the cat. converter and making bad smell. The old plugs looked good...except dark...like too rich mixture. Reread this whole thing tonight. I didn't follow up with any MAP sensor change. I don't have one, so I might have to go get one tomorrow... Quote Link to comment Share on other sites More sharing options...
the3rsss Posted January 20, 2012 Share Posted January 20, 2012 I think your going down the wrong road with the iac. They either stick or they dont. Easy check, does it turn easily or bind? And again, they produce either a very high or very low idle. I posted on this thread last week.Are your plugs ngk? You replied your plugs were "ok" and the wires were "ok". These engines have to have ngk plugs and a quality set of wires. Basics!! Vac leak, dirty throttle body, vac leak! Oh did i mention vac leak? Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 20, 2012 Author Share Posted January 20, 2012 Well, I think the problem is solved.... Yes, a couple people mentioned vacuum leak. Well, I looked over all the vacuum lines, and checked and double checked, but couldn't find any problem. So, today I'm focusing on MAP sensor, and I find one on Ebay, and I'm looking in that area a couple times. There are no cracked hoses there either, BUT, one of the two short hoses that are in that area, the one connected to the little plastic filter on the long vacuum line to the engine.... that dumb little hose comes right off the little pipe it is attached to. It had expanded and gotten hard. Hmmm. So I got some hose and replaced it. I checked the other short one that goes to the MAP sensor itself, and it wasn't as bad, but was also hard and easy to pull off. So I replaced that one also. Probably not more than 8" total of hose. So, it's about 25 degrees here, and I start the car and put it in gear right away.... and voila! No stall. So I put it in drive... no stall. I backed out of the driveway and drove it around the neighborhood, and there was not a hesitation or hint of stalling. SO, I think this is fixed, and you guys that kept mentioning vacuum were right. The test of this is that I will start it and drive it a couple mornings to verify it. A couple times before when I thought that it was fixed it turned out I was wrong. In the IAC area, I had taken it off and cleaned it the other day, and it really wasn't dirty or sticking at all. I did reset the solenoid on top close to where it had been. I will see how the car idles (rpm) and drives in the next couple days, and go from there with the IAC. I had put Allen socket screws on it, so it is easy to loosen it and tighten it. I don't know if the ECU in this car has to "learn" to reset itself or not. I did have the battery out for a couple hours yesterday doing the valve cover seals. We'll see how the car runs in the next couple days. Again, thanks everyone for the comments and the persistence on the vacuum issue. If I was to pick a place where there would be vacuum hose problems, it would be near the engine, where it is hot and there is vibration. These little hoses are on the firewall away from all that, but it is a 17 year old car, and I guess with no clamp, once that rubber aged and got hard, it just loosened up. Kind of what I found with the sunroof drain hoses. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 20, 2012 Author Share Posted January 20, 2012 I think your going down the wrong road with the iac. They either stick or they dont. Easy check, does it turn easily or bind? And again, they produce either a very high or very low idle. I posted on this thread last week.Are your plugs ngk? You replied your plugs were "ok" and the wires were "ok". These engines have to have ngk plugs and a quality set of wires. Basics!! Vac leak, dirty throttle body, vac leak! Oh did i mention vac leak? Oh, you would be horrified, but I just put Autolite plugs in it. Why? I recently took a set of double platinum Autolites out of my Ford Windstar van that were 10 years old, and they could have gone another 20 years... no degradation of the electrodes, no change of gap, nothing. The previous owner had put champion double platinum in this Subaru, and they were fine also, except a little dark. I would have left them in except that I broke one. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted January 20, 2012 Share Posted January 20, 2012 NGK or Denso only. Bosch copper if you must. (not the platinums, the little electrode buried in ceramic burns down) Subaru has specifically warned against champion plugs in some of their literature. Quote Link to comment Share on other sites More sharing options...
naru Posted January 20, 2012 Share Posted January 20, 2012 Subaru has specifically suggested which Champion plugs to use in my owners manual. Don`t get hung up on brands. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 21, 2012 Author Share Posted January 21, 2012 Well, wrong again. It's not fixed. Started it this morning. About 25 degrees outside. Put it in gear and it stalled.... Quote Link to comment Share on other sites More sharing options...
the3rsss Posted January 21, 2012 Share Posted January 21, 2012 Check for spark at all 4 cyl. Do it cold. Check the plug wire resistance. Get a squirt bottle and moisten the coil and wires. See if it reacts at all. The Iac is controlled by the ecm which gets its info from the coolant temp sensor. If the sensor goes (rare) the ecm might think the car is warm. Have you changed the fuel filter? Air filter? Still think its a vac leak. If one of those small vac hoses are hard I'd replace them all. Quote Link to comment Share on other sites More sharing options...
the3rsss Posted January 21, 2012 Share Posted January 21, 2012 I would only use ngk plugs. This ain't a Ford v6. Just my opinion. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 22, 2012 Author Share Posted January 22, 2012 Check for spark at all 4 cyl. Do it cold. Check the plug wire resistance. Get a squirt bottle and moisten the coil and wires. See if it reacts at all. The Iac is controlled by the ecm which gets its info from the coolant temp sensor. If the sensor goes (rare) the ecm might think the car is warm. Have you changed the fuel filter? Air filter? Still think its a vac leak. If one of those small vac hoses are hard I'd replace them all. I checked the voltage at the MAP sensor today. The Haynes manual says it should be 3 volts at idle, but this one is 1.5 volts. I ordered another MAP sensor from a guy on Ebay. If you felt this car die when you put it in gear, you would never talk about the wires or the plugs. It runs great when started, it runs great when warm. It's not the plugs or the wires. I put in a new air filter. Someone mentioned pulling the plug on the upstream o2 sensor. I will do that also. I am open to vacuum leaks still, but if it is that, I'm wondering if it is a hidden line somewhere? If anyone knows of one running somewhere that it out of sight and prone to be bad, let me know. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 22, 2012 Author Share Posted January 22, 2012 I would only use ngk plugs. This ain't a Ford v6. Just my opinion. Is there something about NGK plugs that is different from other plugs? I'm really impressed with double platinum plugs. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 22, 2012 Author Share Posted January 22, 2012 Decided to check the front oxygen sensor last night. There is 12 volts at the connector, but the heater resistance on the sensor only measured 3.3 ohms, when Haynes says it is supposed to measure 30 ohms. I left the sensor unplugged. This morning I started the car and put it in gear and it drove immediately without stalling. Drove it around the block. So I will be buying an O2 sensor. I saw a comment on the Advance Auto Parts (or maybe it was Pep Boys) site that if you buy the Bosch sensor that doesn't come with a connector, that the sensor is physically too long to fit the space. The photo looks longer than the exact replacement one. I wonder if this is true, or what? A number of people sell this sensor. It's about $40 cheaper. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 26, 2012 Author Share Posted January 26, 2012 Got another MAP sensor and tried it out, but it did almost exactly the same as the one I had. I did find if I disconnected the vacuum entirely that it registered around 3.7 volts. It seems that the vacuum reaching this sensor is controlled by the solenoid right beside it. I am going to get another one of those and try it out. I did take that solenoid apart, and I don't see anything wrong with it. I put 12 volts on it and got the little piston inside to move if it is in there by itself, but if the spring is in place the piston can not overcome the spring, even though it is a very light spring. Anyway, we'll see what happens with a different one when it gets here. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 26, 2012 Share Posted January 26, 2012 Decided to check the front oxygen sensor last night. There is 12 volts at the connector, but the heater resistance on the sensor only measured 3.3 ohms, when Haynes says it is supposed to measure 30 ohms. I left the sensor unplugged. This morning I started the car and put it in gear and it drove immediately without stalling. Drove it around the block. So I will be buying an O2 sensor. O2 sensors will not affect engine running when cold. The sensor element does not produce electricity until it is warm (approx. 600 degrees), so the ECU does not take O2 sensor readings into account for determining the fuel mixture when the engine is cold. The solenoid you took apart is called the pressure sources switching solenoid. It flips between intake and atmospheric pressure to help the ECU determine air density. On some cars it also measures fuel tank pressure through the evap lines. Just depends on what time the solenoid is activated, in conjunction with the evap purge control solenoid. Basic solenoid operation can be tested by connecting the test mode connectors then turning the ignition ON. The solenoid will click in roughly 1 second intervals and air can be pushed/pulled through the ports on the solenoid. The port to the Map sensor will always be open, but the upper port and the vacuum port to the engine will switch on/off in unison. Air should only move through one at a time. If air moves through both the valve is faulty. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 31, 2012 Author Share Posted January 31, 2012 O2 sensors will not affect engine running when cold. The sensor element does not produce electricity until it is warm (approx. 600 degrees), so the ECU does not take O2 sensor readings into account for determining the fuel mixture when the engine is cold. The solenoid you took apart is called the pressure sources switching solenoid. It flips between intake and atmospheric pressure to help the ECU determine air density. On some cars it also measures fuel tank pressure through the evap lines. Just depends on what time the solenoid is activated, in conjunction with the evap purge control solenoid. Basic solenoid operation can be tested by connecting the test mode connectors then turning the ignition ON. The solenoid will click in roughly 1 second intervals and air can be pushed/pulled through the ports on the solenoid. The port to the Map sensor will always be open, but the upper port and the vacuum port to the engine will switch on/off in unison. Air should only move through one at a time. If air moves through both the valve is faulty. Fairtax4me, I got a couple used pressure sources switching solenoids. I tried my test of connecting it up to 12 volts, and got a healthy "click" so I know that the piston inside is moving. I installed it, but the MAP sensor is still doing exactly the same thing... reading 1.6 volts, and not really changing any with engine rpm. There are 3 hoses to the pressure sources switching solenoid... one to engine vacuum, one to the MAP sensor, and a 3rd one that goes under the intake manifold, AND SEEMS TO BE CONNECTED TO YET ANOTHER SOLENOID!!!!!!!!!!!!! Are there no end of these solenoids! Now I am wondering if that is working, because with that hose disconnected there does not seem to be any vacuum there. Of course I don't know what is supposed to be happening at that hose. I tried to look on a parts site... and that solenoid might be called "duty solenoid" but I'm not sure. Anyway, could this be a problem... what is it really called, and is there a way to test it? Thanks for your help on the MAP terminology... Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 31, 2012 Share Posted January 31, 2012 The one under the manifold is the evap system purge control solenoid. This solenoid can be tested in a similar manner. With the key on in test mode blow air through the solenoid. As the solenoid clicks air should flow then stop corresponding with solenoid operation. These solenoids have a habit of clogging with carbon and air will flow at all times regardless if the solenoid is open or closed. It can generally be disassembled and cleaned out when this happens. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted July 7, 2013 Author Share Posted July 7, 2013 Just to put this to bed... I did a lot of work on the car but I think the bottom line cause of the problem was that the IAC control was set wrong. A number of people mentioned this. At some point when the family member in our house with the similar car was here I compared the position of the top of the IAC with our other car, and changed the problem one to match the good one. I think that pretty much took care of it. One other note: don't ever loosen the screws on the top of your IAC. It takes dealer equipment to get it set properly. I was mislead by an online article and should never have touched it. Quote Link to comment Share on other sites More sharing options...
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