mjwhere
Mar 6, 2010, 01:56 PM
Honda engine idle goes up (2000 RPM) & down (1200 RPM) when warm (6 cyl 98 accord)
TxGreaseMonkey
Mar 6, 2010, 03:21 PM
. Clean or replace the Idle Air Control Valve (IACV):
https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-7.html#post1054149
. Clean the throttle plate and throttle body. Afterwards, clean the air box and replace the air filter.
. Replace the PCV Valve.
If the problem persists, focus on the Ignition Control Module--it may need replacing. These links will provide the necessary background, perspective, and how-to:
https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-3.html#post260436
https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-4.html#post265896
biff26
Mar 7, 2010, 08:28 AM
Check fast idle valve sometimes they stick open