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Rough Idle 850 1994

Starts up idle's a tad off, then once you put it in gear the idle gets real rough. Once you are driving or apply any gas it seems to run just fine.

I have checked very thoroughly for a vacuum leak with several different mediums and I get no reaction.

I have cleaned the MAF and this has had no effect.

I unplugged the O2 sensor and nothing changes (probable cause?)

I pulled the codes from the OBD-I box and received a 2-3-2 from A2 and a 2-4-1 from A6 which I suspect is due to the manifold not having an EGR tube receiver so the EGR tube is just hanging in the breeze however it has been like that for almost a year so I think the 2-3-2 is the cause. But what is causing it? When I cleared the A2 codes the engine bogged way way down for about 10 sec and then went back to the sort of rough idle, I then drove it for 20 miles and the CEL did not come back.

PCV system has been serviced and checked regularly. Spark plugs and under a year old and are of premium quality and we only use premium gas and the air and fuel filter are fairly recent.

As always thank you for your help!

-Chris








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    Rough Idle 850 1994

    Hi,
    one of my most difficult to find vacum leak was not the hoses but the air intake gasket after 10 years normal situation.
    check by spraying soap liquid around and listen to the idle and you might identify leaking gasket.
    br Tapsa








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    Rough Idle 850 1994

    Is it possible that the idle control motor is very dirty? That would explain the worsening when the car is put in gear and smooth running when at speed.

    The only good way to check the O2 sensor is with a very sensitive multimeter.

    You also might check the vacuum line for the fuel pressure solenoid, there must not be any gasoline in it. Check the ECT sensor and make sure it is within spec.
    --
    My name is Klaus and I am a V♂lv♂holic








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      Rough Idle 850 1994

      Let me check those things and I'll get back to you








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        Rough Idle 850 1994

        I just took out the Idle control valve and cleaned it a bit and put it back in, no difference. Checked the vacuum to the solenoid doesn't seem to be faulty or clogged. and wouldn't my temp gauge not work if the ECT was bad?







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