psu_Crash Posted September 8, 2010 Report Share Posted September 8, 2010 (edited) I got sick of my foot being the idle controller while I warm up so I bought a Bosch 3-wire IACV off Ebay, Part# 0 280 140 505. Instead of drilling and tapping the plenum somewhere I thought it was a much better idea to modify the throttle spacer I was already using. Modified the throttle spacer to connect the IAC. The barb fitting is 3/4" OD to match the idle air valve. Made the barb on a lathe from a piece of 1/2" electrical conduit. Modified MS with a TP120 transistor to handle the current load of the new valve. Placed a diode across the coil of the valce that is controlled my MS. The other coil is connected to ground through a 35Ω 50W resistor that I also bought off Ebay for about $5. I'll have to grab some installed pics. http://a.imageshack.us/img836/5026/img00274m.jpghttp://a.imageshack.us/img835/8015/img00278v.jpg It works beautifully in warm up mode. For some reason it does not work in closed loop, at all. While in closed loop the Idle DC drops to 0 right away when the car starts. No idea what I have setup wrong there but it works just like it should while on the simulator. Anyone else running this valve and have settings to share? Here are my current settings. http://a.imageshack.us/img826/3371/iacsettings9810.jpg I realized on the way into work tonight (while racing a Mustang) that the valve DOES NOT SEAL 100% against boost, or vacuum for that matter. I currently have the intake to the valve just open to atmosphere and at full boost I get terrible fluctuations, no matter where I have max boost set at. In the pic below max boost should be 14psi. So I am going to weld a bung onto the IC pipe between the IC and throttle plate. That should take care of the problem, I hope. http://a.imageshack.us/img826/3504/lowboostoscillations.png Edited September 8, 2010 by psu_Crash Link to comment Share on other sites More sharing options...
pure_insanity Posted September 8, 2010 Report Share Posted September 8, 2010 correct me if im wrong here but... closed loop is warm up mode and open loop means the ecu is open to what the sensors tell it that it needs. am i right? if so youve got it backwards. Link to comment Share on other sites More sharing options...
spoon32 Posted September 8, 2010 Report Share Posted September 8, 2010 Warmup is open loop. It goes off your PWM vs. CLT table and nothing else. Closed loop will allow the ECU to read idle RPMS and make adjustments to the PWM on the fly in order to maintain your RPM vs. CLT table. Link to comment Share on other sites More sharing options...
spoon32 Posted September 8, 2010 Report Share Posted September 8, 2010 Also.... as I have mentioned in my thread, I am using a 2-wire PWM and having troubles with it. Is there an advantage to using a 3-wire over a 2-wire unit? Link to comment Share on other sites More sharing options...
psu_Crash Posted September 9, 2010 Author Report Share Posted September 9, 2010 Warmup is open loop. It goes off your PWM vs. CLT table and nothing else. Closed loop will allow the ECU to read idle RPMS and make adjustments to the PWM on the fly in order to maintain your RPM vs. CLT table. Correct Also.... as I have mentioned in my thread, I am using a 2-wire PWM and having troubles with it. Is there an advantage to using a 3-wire over a 2-wire unit? The only reason I went with the 3-wire is because the part# was specifically listed as tested and working on msextra.com I have also heard that the 3-wire responds faster since it has the other coil that works like a spring return. Although I don't know if there is any truth to that. Spoon what issues are you having with the 2-wire? Does it work in open loop?Doing some research over at msextra forums I see some people are running a Dashpot Idle Activation Adder up as high as 650. I haven't tried that, but it makes me think that maybe I don't fully understand what is going on there. Still ... mine works fine on the JimStim, just not in the real world for some reason. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 9, 2010 Author Report Share Posted September 9, 2010 After installing a check valve between the intake and the valve I am still getting horrible boost surges. Went over everything quick and it seems fine.... crap ... what have I done this time!? Time for a boost leak check I think. Link to comment Share on other sites More sharing options...
jahjah Posted September 18, 2010 Report Share Posted September 18, 2010 very cool man. I've never had idle problems *knocks on wood* through the last few winters. Link to comment Share on other sites More sharing options...
psu_Crash Posted September 18, 2010 Author Report Share Posted September 18, 2010 very cool man. I've never had idle problems *knocks on wood* through the last few winters. Thanks! It works great in warm up mode. Not sure exactly what it is but my car idles like total crap and will die when it's cold. Or below about 140F for that matter. So idle control keeping things about 1500rpm on startup and decaying works great!The boost issue went away when I rebalanced the front tires too. Odd but I'm just going to pretend it never happened.Jusy took the IC pipe off to weld a bung for the IAC to pull air from. I'll grab pics before it all goes back together. Really happy with the way my car is turning out! Link to comment Share on other sites More sharing options...
psu_Crash Posted October 15, 2010 Author Report Share Posted October 15, 2010 Still haven't taken some installed pics but I'm having the boost oscillation issue again. On the way to Charlie's meet a few weeks ago it started acting up so I turned off the HKS EVC and it held rock solid at 10psi, as it should with the spring in my Tial WG. I took a Mityvac to all of the EVC lines and everything checks out perfect. Went through the teaching process for the EVC a couple times to with no luck. How could installing this IAC have screwed up my ability to control boost!?? The air into the valve is now plumbed into the IC pipe before the throttle plate and the outlet is in the spacer as shown above. I'm lost, any ideas?? Link to comment Share on other sites More sharing options...
pure_insanity Posted October 15, 2010 Report Share Posted October 15, 2010 Still haven't taken some installed pics but I'm having the boost oscillation issue again. On the way to Charlie's meet a few weeks ago it started acting up so I turned off the HKS EVC and it held rock solid at 10psi, as it should with the spring in my Tial WG. I took a Mityvac to all of the EVC lines and everything checks out perfect. Went through the teaching process for the EVC a couple times to with no luck. How could installing this IAC have screwed up my ability to control boost!?? The air into the valve is now plumbed into the IC pipe before the throttle plate and the outlet is in the spacer as shown above. I'm lost, any ideas?? sort of makes me think that maybe the iac is screwing with the map readings. take a close look at it in a datalog. Link to comment Share on other sites More sharing options...
NotStock88 Posted October 15, 2010 Report Share Posted October 15, 2010 I too am experiencing the complete crap idle when its cold and just about any time the temp dips below regular running temps. I am bidding on a bosch unit like yours on eBay now and hope it works out. Please keep us posted on how this pans out. Link to comment Share on other sites More sharing options...
pure_insanity Posted October 16, 2010 Report Share Posted October 16, 2010 (edited) ive been running this valve and letting it bypass a little air, however its got too small an orifice to really bring the rpm up enough. it helps but needs to be bigger to allow more http://i214.photobucket.com/albums/cc263/pureinsanity1/mpi%20pics/coilpackandhood009.jpgso i had been thinking about a bigger valve, something like this.valve however, what do you guys see as being the benefit of the pwm valve versus a solenoid valve? or does it just boil down to what works for you? Edited October 16, 2010 by pure_insanity Link to comment Share on other sites More sharing options...
psu_Crash Posted October 16, 2010 Author Report Share Posted October 16, 2010 The PWM valve starts at fast idle and gradually ramps the rpm down as you warm up. Just like a "normal" car. I ran a solenoid valve for a while before and it did work but this is much smoother. With the 3/4" fittings on this valve it fill flow enough air to bring the cold idle up to near 4k if so desired. I have taken a half dozen datalogs of this oscillation phenomenon (see above) nothing jumps out as odd to me. I'll post up a link to some logs tomorrow. Really appreciate the input guys Link to comment Share on other sites More sharing options...
questian Posted October 16, 2010 Report Share Posted October 16, 2010 Hey fellas its all about the tuning,i have a valve on my setup but only comes on with the ac at idle i leave my car sitting for days at a time and it still crank and idle on the first turn key.What you have to do is first get your cold cranking pulse set then your ASE set then you can start that bad ..s karr and drive away every time Link to comment Share on other sites More sharing options...
psu_Crash Posted October 16, 2010 Author Report Share Posted October 16, 2010 Hey fellas its all about the tuning,i have a valve on my setup but only comes on with the ac at idle i leave my car sitting for days at a time and it still crank and idle on the first turn key.What you have to do is first get your cold cranking pulse set then your ASE set then you can start that bad ..s karr and drive away every time Care to share your setup? Always interested in taking a look at another guys tune. Link to comment Share on other sites More sharing options...
pure_insanity Posted October 20, 2010 Report Share Posted October 20, 2010 Care to share your setup? Always interested in taking a look at another guys tune. yea, i would be interested to see what valve you are running. and how exactly did you set it up to work only with the a/c on ? Link to comment Share on other sites More sharing options...
psu_Crash Posted October 20, 2010 Author Report Share Posted October 20, 2010 (edited) Here's a link to a couple logs I took the other day. I'm about ready to take the whole IAC setup off and see if my car returns to normal. Always something with these cars Cold Startup. Never noticed this before and not sure what causes the injector PW to jump up after a few seconds. I thought ASE but it shows that kicking in before the PW increases. Going to have to investigate this more. http://www.mediafire.com/?ztj9jdjrukamrpk Log of a Cruise. Mostly just cruising but I did turn on the EVC at one point (go to max boost) with no luck. http://www.mediafire.com/?ce9c3c5ojk23x0l Pure_insanity, I wish my throttle body had the port that bypasses the butterfly like yours. I may have to go junkyard shopping to find one if taking out the TB spacer fixes my problem. Edited October 20, 2010 by psu_Crash Link to comment Share on other sites More sharing options...
psu_Crash Posted November 17, 2010 Author Report Share Posted November 17, 2010 Pics of the install. The hose I used was just what I had laying around. It's rated for 40psi but maybe it is flexing and causing the problems?? I'm about to take the whole setup out if I can't get this straight. Link to comment Share on other sites More sharing options...
psu_Crash Posted November 18, 2010 Author Report Share Posted November 18, 2010 http://img266.imageshack.us/img266/5817/iacinstall2.jpghttp://img707.imageshack.us/img707/5189/iacinstall1.jpg Link to comment Share on other sites More sharing options...
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