1999 Honda Accord Loping (uneven ) idle

1999 HONDA ACCORD
145,000 MILES • 4 CYL • FWD • MANUAL
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RANDYWNELSON
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I removed the intake manifold to clean the EGR path (which was completely plugged) from EGR valve to intake manifold. I cleaned everything including inside the intake manifold with Gumout carburetor cleaner. I reassembled the intake manifold. It starts fine and idles fine until the engine warms up. When warm it idles (lopes) between 1500 and 1000 psi. The engine dies if I try to rev it or turn on the air conditioner.

Did crud possibly get into the injectors? Did I damage a sensor? What should i do?
Jun 1, 2010 at 8:45 AM
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KHLOW2008
  • ASE Certified Mechanic
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Hi randywnelson,

Check if there are any vacumn leakages at the manifold, especially between the gaskets.
Jun 1, 2010 at 12:17 PM
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RANDYWNELSON
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what is a good method to check for leaks around the manifold. i put on new gaskets both at the throttle body and top of intake manifold
Jun 4, 2010 at 8:00 AM
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KHLOW2008
  • ASE Certified Mechanic
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  • ASE Certified Mechanic
Try spraying carb cleaner around suspected leaks and if the engine idling changes, leaks are present.

Any vacumn leakage woudl cause the idling to increase.

If you hacd cleaned the throttle body, try readjusting the idling speed.
Jun 4, 2010 at 10:16 AM
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RANDYWNELSON
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saga continues. I found that my IAC was not connected. Car still idles/runs very rough. Now I have p0500 error code (vehicle speed sensor). Any ideas
Jun 11, 2010 at 8:49 PM
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KHLOW2008
  • ASE Certified Mechanic
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  • ASE Certified Mechanic
After reconnecting the IAC, is there any changes in the idling speed?

Did you clean the IAC?

I have emailed you the diagnostic files for P0500. Hope it is helpful.
Jun 18, 2010 at 7:34 AM
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