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    #16
    Thanks for all the useful info! They are saying -30 wind chill tonight


    Motor City Patrick
    1988 MGM

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      #17
      Had a problem once with the IAC on one of my 96s. Left FL when it was 62 degrees. Drove home straight through to NE Indiana and when I got there it was 4 degrees. Next morning, car wouldn't start. Feathered the pedal and it acted like it wanted to stay running so I knew it was the IAC. Swapped it out and all was well. I think these things can be somewhat temperature sensitive. Maybe it missed FL.
      Nick


      Past: 1967 Continental convertible, 1987 TC Cartier, 1996 TC DAE & Signature, 2002 LS V8, 2006 Zephyr, 2010 MKZ AWD, and many more.....
      Current: 2010 F-150 Platinum Supercrew 4x4
      Wanted: 1967 or 1969 Contnential sedan
      Only in my dreams: A Continental Mark II

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        #18
        I have had mine stick a couple of times in freezing cold temps, when I get to where I'm going the idle is high. Last year when it did that I replaced it with a spare that I had and it was fine. This year that replacement is doing the same but not on every trip. I'm starting to think that the one I replaced last year may not have been bad but that it just didn't like the cold and perhaps cleaning it might have helped. If this one keeps it up I'll try cleaning it and see what it does, but it doesn't act up when the temps are in the 20s or above. I know in the summer when I have issues with the IAC cleaning it has always helped me so the same may prove true during the winter.
        Vic

        ~ 1989 MGM LS Colony Park - Large Marge
        ~ 1998 MGM LS - new DD
        ~ 1991 MGM LS "The Scab"
        ~ 1991 MGM GS "The Ice Car"

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          #19
          Originally posted by HiFiMerc View Post
          Do not apply voltage to that thing. You'll fry it. Ask me how I know.

          The ECM doesn't apply steady voltage to it, it pulses it if I recall.
          LoL. Thanks, I would've tried that with a 6V battery on a spare.

          Originally posted by 1988 Grand Marquis Pat View Post
          Thanks for all the useful info! They are saying -30 wind chill tonight


          Motor City Patrick
          Yup, pretty cold. Old gal fired up and did her thing without incident.
          1985 LTD Crown Victoria - SOLD
          1988 Town Car Signature - Current Party Barge

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            #20
            I have noticed mine works when it is above 5 degrees. When its -10 it idles high, then idles low when warmed up.


            Motor City Patrick
            1988 MGM

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              #21
              Ashley's TC & mine do the same thing, more like idles at the fast setting for a bit longer (15-20 seconds) before it calms down. If I were to fire up my Firebird with it's TBI set-up I'm sure it would idle around 1700 RPM for a good 1-2 minutes before it began to back off.
              1985 LTD Crown Victoria - SOLD
              1988 Town Car Signature - Current Party Barge

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                #22
                Originally posted by HiFiMerc View Post
                Do not apply voltage to that thing. You'll fry it. Ask me how I know.

                The ECM doesn't apply steady voltage to it, it pulses it if I recall.
                Awesome. Thanks! You probably just saved me from blowing up an IAC down the road.

                I figured that because it was a coil it would work somewhat like a relay. I guess not.

                '78 LTD | '87 Grand Marquis | '89 Crown Vic (RIP) | '91 Grand Marquis (RIP) | '94 Town Car (RIP) | '97 Town Car (RIP)

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                  #23
                  They use a pulsed current, steady DC smokes them. Does the same thing to the EGR regulator. I learned that the hard way too. You can sort-of monitor them with an analog voltmeter though. Its not quite accurate but it will show higher voltage with a longer duty cycle. A better way to do it is with a meter that either reads duty cycle directly or with a scope. I lack those, but I've got 30 year old multimeters and long wires.
                  86 Lincoln Town Car (Galactica).
                  5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                  91 Lincoln Mark VII LSC grandpa spec white and cranberry

                  1984 Lincoln Continental TurboDiesel - rolls coal

                  Originally posted by phayzer5
                  I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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                    #24
                    Originally posted by gadget73 View Post
                    All thats in there really is a solenoid with a ball on the end of it.
                    Originally posted by gadget73 View Post
                    They use a pulsed current, steady DC smokes them.
                    Interesting...I always thought the IAC was actuated by a stepper motor, not a solenoid (I believe it may be stepper on other EFI engines). The more you know! So the ECU just increases the duty cycle of the pulse in order to draw the plunger further out?
                    RyPow
                    1987 LTD Crown Victoria LX sedan - The "Sand Box" - 73K, towing package
                    1987 LTD Crown Victoria LX Tutone Tudor - '96 Explorer 5.0 + 5spd swap in the works
                    1985 Lincoln Town Car Cartier - previously owned by "navguy12" from thelincolnforum.net
                    2007 Lincoln Town Car Signature Limited, 102k, daily driver
                    2006 Mercury Grand Marquis LS, 115k, winter beats
                    1977 Lincoln Continental Town Car, 42k
                    2012 F-150 5.0L 4x4, HD payload pkg (towing/hauling)
                    2015 Toyota RAV4 XLE AWD (better half's)

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                      #25
                      yep, exactly so. It returns to the closed position with a spring. The longer the duty cycle, the more it pushes against the spring and opens the thing up further.

                      Later designs might use a stepper motor, but the old EEC IV wasn't quite that sophisticated.
                      86 Lincoln Town Car (Galactica).
                      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                      91 Lincoln Mark VII LSC grandpa spec white and cranberry

                      1984 Lincoln Continental TurboDiesel - rolls coal

                      Originally posted by phayzer5
                      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                      Comment


                        #26
                        The bitch is finding the oem spacer gasket.......
                        Originally posted by 1988 Grand Marquis Pat View Post
                        Can you just buy the gasket at the chain auto parts stores?


                        Motor City Patrick

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                          #27
                          Originally posted by Toploader View Post
                          The bitch is finding the oem spacer gasket.......
                          Fel-Pro makes one part#71216 (302 sefi 1986 to 1991)

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                            #28
                            Or is it possible to cut one from gasket paper?


                            Sent from my iPhone using Tapatalk
                            1988 MGM

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                              #29
                              For the price of a gasket, why bother???


                              "Hope and dignity are two things NO ONE can take away from you - you have to relinquish them on your own" Miamibob

                              "NEVER trade your passion for glory"!! Sal "the Bard" (Dear Old Dad!)

                              "Cars are for driving - PERIOD! I DON'T TEXT, TWEET OR TWERK!!!!"

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                                #30
                                I've never had problems with the gaskets from the part store. Most of the time you don't even need to change it unless you tear it. Worst that will happen is it will suck air and idle high.
                                86 Lincoln Town Car (Galactica).
                                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                                1984 Lincoln Continental TurboDiesel - rolls coal

                                Originally posted by phayzer5
                                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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