mbrickell Posted March 8, 2006 Share Posted March 8, 2006 For those interested in my Loyale issue, some more "progress"... I notice searching that there are a fair number of Loyale stumbling-hesitation issue posts, so perhaps this is of interest or is helpful for some: Quick background. Loyale runs beautifully when cold for 2 minutes or so. After that, hesitation throughout rev range, 15-20% power loss, revs slowly and laboriously compared to quick and smooth when cold. Phase one: replaced o2 sensor. No effect. Also switched out AFM with one from junkyard donor, no change. Phase two: new plug wires, no effect but did not expect one. Phase three: New fuel filter yesterday, no effect. Phase four: dropped entire exhaust system and inspected for cat parts that some suggested were possibly floating around and blocking exhaust. Flashlight shone down rear part showed perfect matrix of cat element with no sign of damage or degradation. No pieces laying around loose. Front part cannot see since pipe is bent, but no loose sounds or any indication cat element deteriorated, broken, etc. Since I have the head to header exhaust gaskets on order but not here yet, now I have a small exhaust noise since the old ones are so crappy and now reused. Yay. Phase 5: Switched out TPS with one from junkyard donor car. No effect. Same issue with poor performance when warm, feels the same. As it was getting dark, I did not have time to adjust the TPS properly so now my idle speed warm is 1200 or so, not 700 as before swap. Still, driving down the road, zero change. Phase 6: coming. New coolant temp sensor on the way from Jamie. New dist cap and rotor on way as well. Aaaargh! Quote Link to comment Share on other sites More sharing options...
azsubaru Posted March 8, 2006 Share Posted March 8, 2006 Well, good luck on finding it. Lots of things seem to cause similar symptoms. One thing I don't know has been mentioned, but maybe the Idle control valve is sticking closed. Mine stuck open, so the usual poor cold performance, but I don't know why it couldn't stick in the other position. Cleaned mine out by spraying lots of carb cleaner down in there, and it fixed it up. Quote Link to comment Share on other sites More sharing options...
mbrickell Posted March 8, 2006 Author Share Posted March 8, 2006 Well, good luck on finding it. Lots of things seem to cause similar symptoms. One thing I don't know has been mentioned, but maybe the Idle control valve is sticking closed. Mine stuck open, so the usual poor cold performance, but I don't know why it couldn't stick in the other position. Cleaned mine out by spraying lots of carb cleaner down in there, and it fixed it up. Hmm...I would think that if a valve was going to stick, it would be in whatever the default position is. So the IC valve is closed when cold and open when hot? Certainly worth a try, not much to lose by cleaning it. Thanks. Quote Link to comment Share on other sites More sharing options...
Holmes Posted March 8, 2006 Share Posted March 8, 2006 The IAC opens mostly when cold, only a little when warm. I didn't notice the mention of plugs in there. I always start at the plugs. Then the cap and rotor, etc. Quote Link to comment Share on other sites More sharing options...
mbrickell Posted March 8, 2006 Author Share Posted March 8, 2006 The IAC opens mostly when cold, only a little when warm. I didn't notice the mention of plugs in there. I always start at the plugs. Then the cap and rotor, etc. I will pull the plugs when I get some time and weather, Thurs or Fri. Good idea, why the heck have I not done that yet? I did notice that when I pulled the exhaust, the inside of the pipes had some black carbon sooty buildup. Not a lot, mind you, but enough to wipe with a finger or something. When you look at the exhaust outlet itself back under the rear bumper, this is not as apparent. Perhaps normal, but thought I'd mention it. Curious now to see what the plugs look like, if they are carboned... Quote Link to comment Share on other sites More sharing options...
Loyale 2.7 Turbo Posted March 8, 2006 Share Posted March 8, 2006 ...Well... I had Exactly the same issue with my EA82... It Definetively Was the Hitachi Carburetor... When they get old, no human being can fix them up; so I "Weberize" my Subie. Got a Weber 32/36 and it Runs Incredible, all issues and problems are gone. Maybe you can try to swap the CrapTachi Carb... Try it. The High Carbon Build Up, tells me that is the Carb the one that makes your engine problems. Good Luck! Quote Link to comment Share on other sites More sharing options...
azsubaru Posted March 8, 2006 Share Posted March 8, 2006 The IAC opens mostly when cold, only a little when warm. Yeah - I got that backwards, but you get the idea. Hmm...I would think that if a valve was going to stick, it would be in whatever the default position is. I agree - but at least for me, things that are hard to fix often turn out to be something that I didn't check because I just knew it couldn't be the cause Quote Link to comment Share on other sites More sharing options...
mbrickell Posted March 9, 2006 Author Share Posted March 9, 2006 at least for me, things that are hard to fix often turn out to be something that I didn't check because I just knew it couldn't be the cause Very true. I found that the car ran mysteriously well today. A lot less hesitation, still some, but better. I drove 30 miles to school, and then about 1/2 way home the check engine light comes on. It is at that point I realize that I forgot to re-connect the O2 sensor after dropping the exhaust last night. So, that was probably my fast idle, not the adjustment of the TPS so much. Funny how no O2 sensor at all made the car run much smoother, esp with a new O2 sensor. I put the dist cap and rotor on today. Unfortunately, Chapmans sent me the incorrect coolant temp sensor, which I have been eagerly awaiting as I figure that has to be the messiah that is going to cure my car ( yeah right ). So, now we wait to straighten that out... arrghh. Quote Link to comment Share on other sites More sharing options...
Holmes Posted March 9, 2006 Share Posted March 9, 2006 I can tell you that when I replaced my CTS it took care of my high idle problem (1100) and the slow return to idle. But it did nothing for my hesitation from a stop or rough idle when warm like I hoped it might. Quote Link to comment Share on other sites More sharing options...
ellets Posted March 9, 2006 Share Posted March 9, 2006 Just for grins, I replaced the engine temp sensor with a 800 ohm resistor. This made a great improvement in engine operation. I just unpluged the 2 wire connector from sensor and stuck resistor in plug. I wonder why a simple brass connector with a thermistor in it (about $5.00 worth) should cost over $75.00. Quote Link to comment Share on other sites More sharing options...
mbrickell Posted March 9, 2006 Author Share Posted March 9, 2006 Just for grins, I replaced the engine temp sensor with a 800 ohm resistor. This made a great improvement in engine operation. I just unpluged the 2 wire connector from sensor and stuck resistor in plug. I wonder why a simple brass connector with a thermistor in it (about $5.00 worth) should cost over $75.00. Interesting. I would guess that when the sensor is cold the resistance is higher, and when hot lower. Adding the resistor basically might be telling the engine that it is cold all the time. Kind of falls in line with my car running well cold but not hot. Hmm...just a guess... Are you driving around with the sensor unplugged and the resistor in place? Quote Link to comment Share on other sites More sharing options...
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