2002 DF140 too fast idle

[BillyG]

I have a DF140 that has run perfect since new that has approximately 625 hours. Since the boat is only used a few times a year and with the quality of today's fuel, I run the engine fuel system dry after each use.

Last time doing this, I turned the ignition switch off but forgot to return the fast idle lever to the closed position.

This time upon start up, the engine went to an 1800 rpm idle. I saw the fast idle lever had been left up and immediately returned it to the closed position. The engine remained "idling" at 1800 rpms and would not come down. Very soon the engine started a .5 second beep @ 3 second intervals. I shut the engine down.

I checked the throttle linkage & connections. They advance and return correctly.
I examined the throttle body and it appears all is working there correctly (shutting completely).
I checked the CTP switch for conductivity and made sure it was on.
Restarted the engine.
I turned the by-pass air screw clockwise and the idle only drop to 1750 when the screw bottomed out. Once again the .5 sec beep @ 3 sec intervals started.

One note said see "IDLE AIR CONTROL SYSTEM" section on page 3.21; but, I don't have a shop manual.

Anyone have any suggestions before I visit a dealer---which is a long way down the road? Thanks.

[hentree56]

you might have a frozen idle air control valve, it opens and closes to control your idle speed. on some engines its in the actual throttle body some its a separate little unit next to the throttle body with a hose connecting it to it. as far as i know the only way of testing it is with the suzuki diagnostics. you could try some deep creep or pb blaster if its the one built into the throttle body, you can spray into the the little hole in the throat of the throttle body. not sure if you can do the same to the one separate from the throttle body.

[BillyG]

Thanks! Remove the idle air control valve from the top of the throttle body. Rod was stuck in the valve. Sprayed with carb cleaner and then coated with Marvel Mystery Oil.

Re-installed. Ran perfectly again. (I love my Suzuki.)

[hentree56]

good stuff thats what i like to hear