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    #1

    Running rough...suggestions on what to test?

    Sometimes when I first start up my car it'll run rough for a few seconds but the main problem is when I'm going 20-30 it'll miss pretty good. Doesn't always do it. The miss comes and goes and sometimes does it at lower speeds and at stop lights.

    I checked the vacuum and it was very steady and pretty high and fuel pressure was 34 psi. I checked the codes this morning (KOEO) and got a 94...probably related to the vacuum solenoid to the charcoal cannister being removed? I tried a cylinder balance test tonight and got codes 41 & 91. With a new fuel pump, filter, and pressure regulator (and 34psi) I wouldn't think it was actually running lean. Especially since it runs good on the highway and if I accelerate. I've been thinking about replacing the O2's but what I'm reading says they usually don't cause the car to run rough so I'm wondering if the cause of the "lean" condition is somewhere else. What sensors could go bad that would cause a miss but not a code? Intake air temp? What about the module on the dist?
    Tags: None
    #2
    94 is Thermactor air bullshit. If the smog stuff is hooked up, then the O2 sensor isn't working right on the drivers side.

    It's still running lean?

    What car is this again?

    Comment

      #3
      Originally posted by 86VickyLX View Post
      94 is Thermactor air bullshit. If the smog stuff is hooked up, then the O2 sensor isn't working right on the drivers side.

      It's still running lean?

      What car is this again?
      Sorry, '87 CV. The smog pump is there but the only vacuum lines coming off the plenum either go to the EGR or the firewall...the rest of the stuff is capped off and the solenoid that went to the charcoal cannister is removed.

      Comment

        #4
        check for burnt fusible links or missing ground for the o2 sensors.
        Give a man a fish and he will be fed for a day. Teach a man to fish and he will promptly forget that he once did not know, and proceed to call anyone who asks, a n00b and flame them on the boards for being stupid.

        Comment

          #5
          Originally posted by cld783 View Post
          check for burnt fusible links or missing ground for the o2 sensors.
          The fusible links up by the starter solenoid? I think one is a little corroded. Do you just match up the wire size to replace them? Are you meaning the ground strap off of the cylinder head? Thanks!

          Comment

            #6
            How old are your plug wires? What you describe sounds suspiciously like ignition issues, usually caused by tuneup parts or maybe a weak ignition coil. If its worse in the rain, then I'd almost guarantee its ignition related.
            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

              #7
              Originally posted by PushnFords View Post
              Sorry, '87 CV. The smog pump is there but the only vacuum lines coming off the plenum either go to the EGR or the firewall...the rest of the stuff is capped off and the solenoid that went to the charcoal cannister is removed.
              Strange, then. You should also have code 44 if you have no vacuum lines hooked up.

              Comment

                #8
                A hundred years ago I had an 86 Towncar that acted like this when I would wash it or it would rain. It straightened up after I replaced the rotor and cap. Just a thought.

                jeremy
                Last edited by jubylives; 04-09-2011, 06:54 AM. Reason: can't spell worth a crap

                Comment

                  #9
                  Originally posted by cld783 View Post
                  check for burnt fusible links or missing ground for the o2 sensors.
                  I've got a 16ga fusible link that looks like it is corroded internally...the black square part is starting to crack open. I'm going to replace that one and the small push on terminal to the starter solenoid...it has some cracks in the insulation.

                  Originally posted by gadget73 View Post
                  How old are your plug wires? What you describe sounds suspiciously like ignition issues, usually caused by tuneup parts or maybe a weak ignition coil. If its worse in the rain, then I'd almost guarantee its ignition related.
                  Plug wires are Napa "Mileage Plus" and less than a year old...same age as the plugs. I pulled the plugs to check the gaps and rerouted the wires to put them in holders when I got the car. None of the plugs looked rich and the wires were all in good shape. The rotor was in good shape so I cleaned it and the cap is a new Accel one I had with brass contacts. Not sure how old the coil is but it has been replaced before. It isn't worse in the rain...the miss is random but getting more frequent. This morning was very damp and overcast...ground was wet, car had dew running off of it, gutters on the house were dripping, etc...and it ran fine on the way to work. I'm only getting 8-10mpg with town driving...I was figuring 18-19 on the one highway trip I did a while back.

                  Originally posted by 86VickyLX View Post
                  Strange, then. You should also have code 44 if you have no vacuum lines hooked up.
                  I have vacuum hoses to the firewall tee, but the one to the charcoal cannister solenoid is capped and the one(s) that went to the solenoids on the fender are all removed and capped. The EGR hose is still there.
                  Last edited by PushnFords; 04-09-2011, 04:01 PM. Reason: combining posts

                  Comment

                    #10
                    The canister solenoid had vacuum source from upper intake. Did you cap that one off?

                    Comment

                      #11
                      Originally posted by 86VickyLX View Post
                      The canister solenoid had vacuum source from upper intake. Did you cap that one off?
                      Is that the little solenoid inline with the hose to the canister? That solenoid is removed and sitting in the garage and the vacuum line is capped. The vent hose coming from the tank is not capped. The only vacuum hose going forward from the intake is the EGR vacuum.

                      Comment

                        #12
                        Originally posted by PushnFords View Post
                        Is that the little solenoid inline with the hose to the canister? That solenoid is removed and sitting in the garage and the vacuum line is capped. The vent hose coming from the tank is not capped. The only vacuum hose going forward from the intake is the EGR vacuum.
                        Stupid question, but you don't have the vacuum applied directly to the EGR valve right?

                        Comment

                          #13
                          Originally posted by PushnFords View Post
                          The fusible links up by the starter solenoid? I think one is a little corroded. Do you just match up the wire size to replace them? Are you meaning the ground strap off of the cylinder head? Thanks!

                          orange wire with a ring terminal bolted to the back of the upper intake stud.

                          the fusible link for the o2 heaters is a 20ga link and i believe is on the drivers side near the relays. if all those check out i'd say your o2's should be replaced, especially if you have never done them.
                          Last edited by cld783; 04-10-2011, 03:56 AM.
                          Give a man a fish and he will be fed for a day. Teach a man to fish and he will promptly forget that he once did not know, and proceed to call anyone who asks, a n00b and flame them on the boards for being stupid.

                          Comment

                            #14
                            If the O2 sensors are bad would it only run rough when warm, cold or both? Just asking as I'm suspiciopus of these on my car.

                            jeremy

                            Comment

                              #15
                              When warmed up, since that's the only time computer looks at them.

                              Comment

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