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Rough Warm Up 1800 1970

posted by  someone claiming to be farmeronthedell on  Sun Mar 6 13:45 CST 2005 [RELATED]

I've got a '70 1800E that I bought a couple of weeks ago from a friend. I've spent some time trying to understand the DJet system and I've got everything running great except for the idle at warm up.

When I first got it, it would run rough (and rich) for about 5 minutes before settling down, then would run fine.

It has a new aux air valve and new temp sensors, new injector seals, timing is right on, and I tightened up the intake manifold a bit.

I've managed to get that rough idle down to a little less than 2 minutes, but during that time, it runs rough and very rich. It won't idle on its own without holding the accelerator to keep the idle around 2000 rpm.

Once it reaches whatever magic event happens, it smooths out and runs like a champ, and idles just fine. I would like to figure out what's going on and fix it.

Any ideas on what's going on to make it idle so rough and rich for those couple of minutes?

Thanks!!







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    Rough Warm Up 1800 1970

    posted by  someone claiming to be bob on  Mon Mar 7 15:56 CST 2005 [RELATED]

    Maybe your cold start injector is leaking, try pinching it off while the car is warming up.








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      Rough Warm Up 1800 1970

      uid 4846's pic
      posted by  JohnMc on  Tue Mar 8 00:40 CST 2005
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Thu Oct 23 07:42 CST 2014
      [RELATED]

      It only operates while the starter is engaged, so if it was leaking there's nothing to make it stop leaking after a few minutes.
      --
      I'm JohnMc, and I approved this message.








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    Rough Warm Up 1800 1970

    posted by  walrus3 on  Sun Mar 6 14:47 CST 2005
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    last visit: Mon Dec 2 14:20 CST 2013
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    There is a plastic knob on the back of the computer, reachable through a hole
    in the bracket. If you turn that to the left, it may improve the rich idle,
    assuming that there is not another problem. What happens that seems to correct
    the problem is that the auxiliary air valve closes when it gets warm.
    (I have seen very few of these that actually work.) The purpose of the
    auxiliary air valve is to make it idle faster till it warms up.
    You might want to check the connections to your coolant temp sensor and your
    manifold air pressure sensor, including the hose on the MAPSensor.
    --
    George Downs Bartlesville, Heart of the USA!








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      Rough Warm Up 1800 1970

      posted by  farmeronthedell on  Tue Mar 8 01:54 CST 2005
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      Checked all the hoses and connections and all is ok there. Odly enough, the plastic knob that you mention was turned all the way to the right. I backed it off about a half a turn to the left. Maybe it's wishful thinking, but it did not seem to run as rough while warming up. hmmmm

      I'm going to try another half turn at the next warmup and see if it gets any better. I'll keep you posted.








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        Rough Warm Up 1800 1970

        posted by  walrus3 on  Tue Mar 8 02:20 CST 2005
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        last visit: Mon Dec 2 14:20 CST 2013
        [RELATED]

        Careful. It is a potentiometer and it only turns through an arc of about
        300°. Normally that knob has little effect on anything but idle and not
        much there but if everything else is right and that is wrong....
        It might be that a little faster idle overall would be tolerable and if so,
        it will probably help. The slower the idle is, the harder things are to
        control.
        --
        George Downs Bartlesville, Heart of the USA!







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