Idle surge

Dealership can’t figure out the problem with my 2004 Honda Element - high rev’ing idle.



This is a 5 speed manual - when car is moving and out of gear (or clutch pushed in) engine will rev up to about 3300-3600 rpm, and stay there until I stop the car. When car comes to complete stop then idle drops down to normal 700 rpm. Car engine basically races like crazy every time I am coming to a stop with the clutch pushed in.



Dealership ran Honda diagnostics and didn’t get any codes/alerts, so they returned car and claimed that they couldn’t replicate the problem. As soon as I rec’d back the car (not even out of the dealership parking lot) the very same problem occurred. This is a consistent, not intermittent problem. I went right back, found the dealership mechanic and took him for a drive.



Mechanic immediately noted the uncontrolled high rev, and told me to spray carburetor cleaner down the throttle body - I did this, but no relief.



Since idle speed comes back to normal at full stop I tend to think this is a bad sensor problem. At one point I had a MIL light that gave OBD code of P2227 - barometric sensor. MIL light since went off but high idle problem remained.



Thanks for your great show, and any help you can give me!



Lars Andersen