Question about 1987 Honda Civic

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My car is idling at 4000rpm not returning to normal....

When I started my 87 Honda Civic Si this morning, it was idling at 4000rpm. It would not go to normal, so I didn't drive it. My dad changed the oil yesterday. I think he may have knocked off a vaccuum hose but none seem disconnected. Is there anything else? What could it be?

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  • asdfyellow Jun 25, 2009

    Where is that sensor at? and how do I know if it's not good or working?

  • asdfyellow Jun 25, 2009

    thanks for the help. my dad pulled or broke the throttle cable on my car and just readjusted it. So soon enough i'm going to have to buy a new throttle cable. But now its running like normal.



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Sounds like a vacuum hose look hard it may also be the mass air flow sensor

Posted on Jun 25, 2009

  • thomas foster
    thomas foster Jun 25, 2009

    it should be mounted on the intake hoses from the air box to the thoratle body or carb it will have a electrical plug in it unplug it and see if anything changes their is really no way to test it but if u unplug it and car sounds different its may be bad its less expensive than a head gasket because that could be the problem as well but if you just changed the oil and it started acting up it got to be a vacuum or mass flow



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