LeolaPA Posted January 10, 2012 Author Share Posted January 10, 2012 This gets crazier all the time. Drove it home 50 miles last night. This morning, I started it up and immediately put it in gear and it did NOT stall. I drove it 5 miles to work, then at the end of the day I did the same thing, and it also started and drove without stalling. So I am a bit baffled! I think the EGR valve is worth changing. That's my next thing I'm doing. We'll see how it runs tomorrow also. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted January 10, 2012 Share Posted January 10, 2012 In the OP you mentioned 'temp sensor'. That was the one with 2 wires right? Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 10, 2012 Author Share Posted January 10, 2012 Rooster2 I don't know what the cold start sensor is. It does start OK. Starting has never been a part of these problems. 1 Lucky Texan, I replaced the temp sensor which is on the passenger side of the motor and has 2 contacts inside. It was the exact replacement. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted January 10, 2012 Share Posted January 10, 2012 Did you try running it with the front o2 sensor unhooked (don't know if that had a rear o2 or not). Cat in another thread did that to diagnose symptoms kind of like this, and noted it ran OK with the front o2 unhooked, just maybe something quick to try. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 14, 2012 Author Share Posted January 14, 2012 The latest on this: Car did not stall when put into gear on 40 degree morning. Changed PCV valve, and put a little rtv on the valve because the hose was hard and stiff. Checked one plug... it looked pretty good, but I broke it, so I replaced it. This morning car stalled when put into gear (temperature in high 20's.) I kept restarting it, and it did not stall when the rpm had dropped to maybe 1100. At the end of the day, the temp was still in the high 20's, but the car did NOT stall when put into gear... I drove it immediately. Tomorrow I am going to check the vacuum lines at the canister in the back. My daughter did complain about gas smell at start up a while back. If there is a leak back there, maybe that could be part of this. A couple people mention vacuum leaks.... Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 14, 2012 Author Share Posted January 14, 2012 Oh, I found this interesting post elsewhere. The English is a bit odd, but there's some helpful stuff in it: http://www.subarumaniablog.com/problem1.php Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 16, 2012 Author Share Posted January 16, 2012 OK, well, I think this MAY be solved. Yesterday i tried to shift the position of the solenoid on the IAC. It still stalled when put into gear cold. This morning, I though, well, what the heck, I'll turn it quite a bit. So, I did that, and it resulted in a pretty high idle speed when first started, like about 2,500, but I was able to put it in gear and go right away. No stalling. The idle when warm was a bit high though, about 1,000. I drove it to church, and before I left 2 hours later, I shifed that IAC solenoid back a little to see what would happen. It did not stall when put in gear... idle at start up around 2,000, and idle when warm about 750. I started it later in the day after the car was cold, and had good results again. So, I'm going to try this a couple more mornings to determine if it is OK. A few people mentioned IAC, but nobody said anything about the position of the solenoid (or whatever it is) on the top of the IAC, and the position of that in relation to running. Misc other facts... temp today was 18 in the morning. Also, the idle at startup got higher when the solenoid position was shifted clockwise. Quote Link to comment Share on other sites More sharing options...
987687 Posted January 16, 2012 Share Posted January 16, 2012 Why don't you just let the engine warm up for a minute? It's not good to fire it up frozen cold engine at 18 degrees and cruise off anyway. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 16, 2012 Author Share Posted January 16, 2012 Thats good, to warm it up a bit, but this is my daughter's car, and she will be doing student teaching this spring, and she will probably be leaving at the last minute at times, and will want to get on the road. All of our other cars will run when cold...2 Chevy Celebrity Eurosport wagons, a Windstar van, and a 87 BMW 325i. Even my old MGB would run when cold with the manual choke pulled out! Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted January 16, 2012 Share Posted January 16, 2012 It should start and run just fine at 18F and even a lot lower than that even without a block heater. One exception could be if it is very cold but does not have a winter blend fuel (not enough vapor pressure), but on fuel injected vehicles that is rarely an issue. The IACV isn't really supposed to be adjusted like that, it comes preset. But if it is making a difference for you maybe it is plugged up inside or otherwise faulty. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 17, 2012 Author Share Posted January 17, 2012 There are 2 screws on the top that you can loosen and turn the top solenoid, or whatever the proper name for it is. The latest is this: Tonight I went out to test it again, and it would not run in gear again. Stalled about 4 times when I tried it. Temperature was 33 degrees. I called the local Subaru experts, and the one guy suggested that I clean the butterfly on the throttle with carb cleaner. He said it sounds simple, but it might help. So I did that, and we'll see what happens tomorrow. If it stalls again, I might just pull the MAF sensor connector and see if it will run in gear that way. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 17, 2012 Share Posted January 17, 2012 The adjustment on the IAC is to be made only with a scanner that will show the duty cycle of the solenoid. The solenoid affects running conditions as well as idle speed and air/fuel mixture. Set it back in it's original position, and start looking for the vacuum leak that's probably causing it to run that way. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 17, 2012 Author Share Posted January 17, 2012 Fairtax4me, where it was was probably not set by the equipment you mention. I can set it back there based on the clean area under the washer where it used to be. Not sure that it will be correct, since I had it off during the summer of 2010. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 17, 2012 Author Share Posted January 17, 2012 Followup on cleaning the intake area and butterfly: I started it this morning, but it still stalls when put in gear. I pulled the MAF sensor connector, and it still stalls when put in gear. I think I will take the IAC off and clean it next. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted January 17, 2012 Share Posted January 17, 2012 Fairtax4me, where it was was probably not set by the equipment you mention. I can set it back there based on the clean area under the washer where it used to be. Not sure that it will be correct, since I had it off during the summer of 2010. Hmmm.....well that might be part of the problem. Here is some info from an Endwrench article These valves are pre-set. Never try to adjust them inan attempt to repair a vehicle. If you find yourself working on a driveability concern and this valve shows signs of tampering, the valve must be replaced. There are no procedures to return it to the factory settings. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted January 17, 2012 Share Posted January 17, 2012 I would replace all the PCV hoses, and put good clamps on there ends. Also check the Vac lines for the Fuel Pressure reg, and Evap solenoids. Hard rubber gets cracked and leaks vacuum. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 18, 2012 Author Share Posted January 18, 2012 Hmmm.....well that might be part of the problem. Here is some info from an Endwrench article Seems like SOMEBODY would know how to do it. I had the whole IAC off today, and I have a dc power supply, and I tried a small voltage between the center pin and the outside pin and there was a small movement of the valve. Using the other pin made it move the other direction. I think I used 3 volts. Seems to me that if you applied a correct voltage to get a closed or open condition, that would be all there is to it. True, most people don't have that capability, but I happen to have that item here. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 18, 2012 Author Share Posted January 18, 2012 I would replace all the PCV hoses, and put good clamps on there ends. Also check the Vac lines for the Fuel Pressure reg, and Evap solenoids. Hard rubber gets cracked and leaks vacuum. Good point. I tried to buy some of this hose, but my local shop didn't stock it in that size. for now I put a little RTV on the new pcv because I know that new one did not fit the old hose the same way exactly and will leak. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 18, 2012 Author Share Posted January 18, 2012 http://www.hondata.com/techidle.html found this interesting info today. The throttle position sensor needs to be set correctly. I will look at that tomorrow. I had the IAC off today and cleaned it, but it really didn't need it. I had the engine somewhat warmed up, but not hot. When I took off the IAC the valve was not totally shut. I guess the ECU must send voltage to the IAC to position it closed, then the magnetism just holds it there when you take it off? Quote Link to comment Share on other sites More sharing options...
naru Posted January 18, 2012 Share Posted January 18, 2012 http://www.hondata.com/techidle.html found this interesting info today. The throttle position sensor needs to be set correctly. I will look at that tomorrow. I had the IAC off today and cleaned it, but it really didn't need it. I had the engine somewhat warmed up, but not hot. When I took off the IAC the valve was not totally shut. I guess the ECU must send voltage to the IAC to position it closed, then the magnetism just holds it there when you take it off? You are in more trouble than I thought if you are using Honda service info to fix your Subaru. Knock yourself out w/some real Subaru info. http://www.finleyweb.net/JonsStuff/SubaruDocumentation.aspx Don`t know if it will help you find the vacuum leak though. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 18, 2012 Author Share Posted January 18, 2012 You are in more trouble than I thought if you are using Honda service info to fix your Subaru. Knock yourself out w/some real Subaru info. http://www.finleyweb.net/JonsStuff/SubaruDocumentation.aspx Don`t know if it will help you find the vacuum leak though. Thanks, but I wasn't using it for the specific info, just for the principles involve with how they interact. I have the Hayes manual that I will use to set the throttle position sensor, or check it tomorrow. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted January 18, 2012 Share Posted January 18, 2012 Seems like SOMEBODY would know how to do it. I had the whole IAC off today, and I have a dc power supply, and I tried a small voltage between the center pin and the outside pin and there was a small movement of the valve. The Endwrench info doesn't mean it can't be done/recalibrated, it's just saying Subaru does not supply any service information to do it, i.e. they do not consider it a field calibratable device. I though I read somewhere it drives it with a square wave of varying duty cycle, much like the automatic transmission solenoids. Quote Link to comment Share on other sites More sharing options...
LeolaPA Posted January 18, 2012 Author Share Posted January 18, 2012 The Endwrench info doesn't mean it can't be done/recalibrated, it's just saying Subaru does not supply any service information to do it, i.e. they do not consider it a field calibratable device. I though I read somewhere it drives it with a square wave of varying duty cycle, much like the automatic transmission solenoids. When I was a kid, I had a single channel radio control outfit that had something called an "Adams Actuator" instead of a servo to control the tail. It was a similar thing... a couple magnets and a coil. If you put power to it, it would turn and stay in one position. It could be that this IAC takes some kind of square wave... I don't know, but with just 3 volts dc it moved maybe 0.080 and stayed there until the power was released. Someone gave me the name of a guy in California who does some hi-tech stuff with cars, so I am going to call him later. The bad thing is that if he says... OH yeah, just set it with x volts to certain pins, it means that I have to take it off again..... Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted January 18, 2012 Share Posted January 18, 2012 That sounds interesting! Let us know what you find out. I'm guessing it is set to allow a certain amount of air through all the time, like just below the absolute minimum the vehicle would need to idle under the best conditions, then the ECU can control the opening to get any additional air needed? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 19, 2012 Share Posted January 19, 2012 I remember reading in an old thread someone talking about the procedure for setting the IAC position. You can check the duty cycle with the Subaru Select Monitor. Here's what the MY1995 FSM has to say about the valve: DESCRIPTION: * Idle air control solenoid valve consists of an air cut valve, duty control valve, intake air passage and a coolant passage. * Air cut valve contains a bimetallic substance which responds to coolant temperature, and a duty control valve which is operated by a signal sent from ECM. * When engine coolant temperature is low, air cut valve is fully opened by the action of the bimetallic substance so that the air flow required for low engine coolant temperatures is maintained. * ECM controls duty control valve to bring the operating engine speed as close to preset idle speed as possible. FSM does not say how to adjust the solenoid. Just putting it back to the clean spots under the screws will get it close enough to work correctly without screwing up anything else. Quote Link to comment Share on other sites More sharing options...
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