1987 Honda Accord Idles too high

1987 HONDA ACCORD
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MRFOX916
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Engine Mechanical problem
1987 Honda Accord 4 cyl Two Wheel Drive Manual

when I get in to my car in the morning and start it. The RPM's go's real high and stays there for about 15 minutes even after driving it about 5 to 10 miles. Then it will go to normal idle. This only happens in the morning or when sitting for a long period of time.
Mar 26, 2009 at 1:00 PM
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RASMATAZ
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Too fast an idle speed. If an engine without computerized idle speed control is idling too fast and refuses to come down to a normal idle speed despite your best efforts to back off the carburetor idle speed screw or air bypass adjustment screw (fuel injection), air is getting past the throttle somewhere. Common leak paths include the carburetor and throttle body gaskets, carburetor insulator spacers, intake manifold gaskets, and of course, any of the engine's vacuum fittings, hoses and accessories. It is even possible that leaky O-rings around the fuel injectors are allowing air to leak past the seals. Another overlooked item can be a worn throttle shaft and a defective idle speed speed control motor/valve stuck in the extended (high idle speed) position/throttle position sensor. Also the throttle plate could be binding in its bore and kinked accelerator cable, coolant temperature sensor might not be operating properly misleading the computer that the engine is still cold and computer throwing fuel at it raising the idle speed.
Mar 26, 2009 at 4:06 PM
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MRFOX916
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OK, so where would you start looking first (the most likely cause). Then after that and so on.
Mar 30, 2009 at 1:51 AM
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RASMATAZ
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Do you have a feedback carbuerator or an EFI fuel system?

Vacuum hoses, intake manifold and the rest of the stuffs I've mentioned above.
Mar 30, 2009 at 1:03 PM
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