kmpdx Posted January 26, 2017 Share Posted January 26, 2017 Hi guys, Trying to get my Loyale to idle at less than 1000 RPMs. Sometimes after driving it and it is warm I turn it off for a few minutes and it will idle at the correct 700 RPMs. The other way to get it to idle at 700 is to disconnect the PCB from the passenger side intake boot. Here are some of the things I have tried. I replaced the IAC valve. The issue is both valves fail the test where the pins on the valve harness to body measures 1MOhm or greater but multimeter shows no continuity. Not sure how this would affect the functionality of the IAC valve but it is my prime suspect. I have tested the Coolant Temp Sensor and resistance does seem to bounce between 280-500 Ohm when car is warm. I have also gone over the vacuum hoses a lot and replaced a few.Including the PCB and most hoses. I am less suspicious of the hoses since it does idle correctly sometimes.I also wonder about the intake gaskets especially on the driver side but am reluctant to change them since one of the bolts looks pretty rotten. I just want to get it through DEQ smog test but eventually want to isolate and repair issue. Think it will pass with one PCV Hose disconnected or at 1000 RPMs? Should I focus on IAC valve? Any feedback is appreciated. Thanks! Quote Link to comment Share on other sites More sharing options...
DaveT Posted January 26, 2017 Share Posted January 26, 2017 1 Meg or greater is saying open circuit or no continuity, which is normal. If the cts ohm reading is bouncing, that is bad. The reading will be different depending on the temperature, and will drift as the parts cool down, but it should be smooth and steady, not bouncing around. Quote Link to comment Share on other sites More sharing options...
kmpdx Posted January 26, 2017 Author Share Posted January 26, 2017 Cool. Going to pick up a new one on hold at parts store today. Will report back in a few hours. Thanks! Quote Link to comment Share on other sites More sharing options...
robm Posted January 26, 2017 Share Posted January 26, 2017 It could be a mechanical problem with the IAC. I have similar problems right now as well. It seems like idle gets better once the car is warm, and I stop for a while. My theory is the IAC is sticky, so it never comes off high idle, until you stop the car and it closes completely (or more so, anyway). Then on restart, it goes to where it should be. I have tried running carb cleaner through mine, and that helped a bit. The fact that you have replaced the IAC already suggests against this, but you could have 2 sticky ones? These things are getting pretty old. A few shots of carb cleaner are worth a try, I think. 1 Quote Link to comment Share on other sites More sharing options...
scoobiedubie Posted January 29, 2017 Share Posted January 29, 2017 I like my idle in the 1200 to 1400 rpm range. Accessories like headlights and A/C will lower the idle when they are turned on. You should set it for the lowest rpm that it currently will get with all accessories on. I believe 800 rpm is minimum in the manual. The higher the rpm, the less likely you will stall the engine when starting out at a stop sign. Quote Link to comment Share on other sites More sharing options...
robm Posted January 30, 2017 Share Posted January 30, 2017 The ECU is really good at maintaining the proper idle speed. It can handle extra loads easily, if the IAC is working properly. In fact, it does it so well, I hardly ever add gas to let out the clutch, just ease it out gently then add gas once moving at idle speed in first. The clutch should last forever if treated like this. Quote Link to comment Share on other sites More sharing options...
kmpdx Posted February 18, 2017 Author Share Posted February 18, 2017 Well, I went to town and replaced intake manifold gaskets and many parts of the vacuum hoses. Also pulled off the EGR and cleaned it and its channels. Idling right around 800 or 900 rpms. Sounds like that is ok. Also replaced many parts of the cooling system and testing the CTS gives a reading of 315 ohms at operating temperature. Two questions. Will I pass a smog test at those RPMs? Do the Ohms on the CTS seems within range? Thanks! Quote Link to comment Share on other sites More sharing options...
kmpdx Posted February 18, 2017 Author Share Posted February 18, 2017 It could be a mechanical problem with the IAC. I have similar problems right now as well. It seems like idle gets better once the car is warm, and I stop for a while. My theory is the IAC is sticky, so it never comes off high idle, until you stop the car and it closes completely (or more so, anyway). Then on restart, it goes to where it should be. I have tried running carb cleaner through mine, and that helped a bit. The fact that you have replaced the IAC already suggests against this, but you could have 2 sticky ones? These things are getting pretty old. A few shots of carb cleaner are worth a try, I think. What you are saying totally makes sense. It is funny that I started with the IAC and did loads of work chasing vacuum leaks. While things are much better looks like I have come full circle back to the IAC! I may try to clean and swap back to the one I removed to see if it makes a change. Thanks! Quote Link to comment Share on other sites More sharing options...
kmpdx Posted March 14, 2017 Author Share Posted March 14, 2017 So I cleaned the old IAC and lubed the little pin where it slides with a little triflo. This valve is working MUCH better! I puled the "new" valve apart and it was missing the o ring that goes between the electrical and mechanical part of the valve which could have helped it not to work. Robm, I do think that these valves get "sticky" and I think it is down in the crimped metal piece beneath the spring. I am going to replace the o ring and lube the "new" one and try it too. Also, if anyone is replacing this valve you need an offset screwdriver to fit the screw between the IAC and the reservoir for the power steering. Otherwise you have to take the whole throttle body off to get to it which is a PITA. I have one that is a ratcheting Bosch but the clearance is so little that I had to grind down the bit until it was super short so that it would fit the space. you NEED to have a tool like that to get the tight screws on this and avoid a much larger disassembly. Now that I have the tool set up it will make it easy to experiment with these valves and swap them out. I will post back with any progress. Quote Link to comment Share on other sites More sharing options...
YnotDIY Posted March 14, 2017 Share Posted March 14, 2017 I posted up about a similar idle issue a couple months ago. I pulled the IAC and cleaned it, fixed the issue for a couple of months it's now back to idling at 2,000 off the clutch and very very I mean VERY slowly goes down to between 500-1000. Just ordered a new IAC off ebay used to swap in. gonna clean and lube it up before it goes on. They definitely get sticky. which for me is revealed by my slow reduction in idle rpms. I imagine that little spring is just moving like molasses in there. could you post a picture of the tool you use to remove the IAC? I took off the throttle body last time and it would be awesome to not have to do that again. Quote Link to comment Share on other sites More sharing options...
robm Posted March 14, 2017 Share Posted March 14, 2017 Hey, kmpdx, if you get 2 working IAC's, can I buy one? Quote Link to comment Share on other sites More sharing options...
kmpdx Posted March 14, 2017 Author Share Posted March 14, 2017 I WILL post a picture later. The way I found out about it was that I was out in my driveway cursing because I had put the throttle body pack on without putting the IAC on first. Fortunately my neighbor loaned me the tool which made it like a 5 minute job! This is similar to the tool I am using: http://www.all-spec.com/Catalog/Hand-Power-Tools/Screwdrivers-Accessories/Screwdriver-Sets/8078-21208?gclid=CjwKEAjwqZ7GBRC1srKSv9TV_iwSJADKTjaDToqL70OPZpyFlKPxHHOlU3jAuiJ-0jl0KM8x0inMmxoC1Zjw_wcB I did have to grind the end down so that bit was super short. There is less than an inch of clearance between the upper right screw and PS reservoir. robm, if it turns out I have an extra IAC I will let you know. I will be at pick-n-pull as soon as one comes up at the South yard and also continue experiment with the current IACs and then let you know. Having that little screwdriver ratchet basically makes the IAC easily maintainable. Quote Link to comment Share on other sites More sharing options...
YnotDIY Posted March 16, 2017 Share Posted March 16, 2017 This is similar to the tool I am using: http://www.all-spec.com/Catalog/Hand-Power-Tools/Screwdrivers-Accessories/Screwdriver-Sets/8078-21208?gclid=CjwKEAjwqZ7GBRC1srKSv9TV_iwSJADKTjaDToqL70OPZpyFlKPxHHOlU3jAuiJ-0jl0KM8x0inMmxoC1Zjw_wcB I did have to grind the end down so that bit was super short. There is less than an inch of clearance between the upper right screw and PS reservoir. Having that little screwdriver ratchet basically makes the IAC easily maintainable. I just (today) swapped the phillips screws out with 8mm machined hex head bolt/screw. even easier to get off now sorry I know it's not applicable to your question, but had to share. 1 Quote Link to comment Share on other sites More sharing options...
kmpdx Posted March 16, 2017 Author Share Posted March 16, 2017 YnotDIY, I was thinking after I wrote that I would do that myself next time. Then I can service this routinely even easier.Thanks! Quote Link to comment Share on other sites More sharing options...
kmpdx Posted March 16, 2017 Author Share Posted March 16, 2017 Wanted to add that valve is working much better but occasionally momentarily lets too much air in an idle bumps a little. Strangely running the blower fan seems to help stabilize the system and keep the idle more around the ideal state. S0 maybe that is related to the electrical system? I thought I might check the voltages at the harness sometime but I probably never will. Just kind of interesting behavior. Quote Link to comment Share on other sites More sharing options...
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