High Idle in 4 cylinder

[flyingkegler]

I have a 1998 Camry LE that began with a hi cold idle (about 1600 rpm) last year and in the last 3-4 weeks it has blossomed to 2600 at cold and then never goes below 2000 at warm idle. It will drop off to 1600 for 1-2 seconds and return to 2000 and will surge like this back and forth every few seconds, but eventually becomes steady at 2000. No CEL light is lit. I disconnected the MAP and shortly thereafter the CEL light went on - so the CEL is working. I have installed a new ICV and it did not change the condition. If i pull the vacuum off the MAP sensor (either at the sensor or at the gas filter on the intake manifold) the idle drops to 700 rpm. This is odd because I thought taking the line off would indicate a open throttle (low vacuum) and hi vacuum would reduce the RPM. MAP sensors are so expensive I don't just want t try one and see. ls is there supposed to be any restriction in the gas filter end where the MAP sensor gets its vacuum supply? I did replace the vacuum lines and tried spraying carb cleaner to identify any vacuum leaks without success. Any ideas? Thanks!