DF 150 - high idle speed - buzzer warning

[orohde]

I just changed battery. The motor started but the idle speed did not go below 1300rpm. The buzzer started to beep, but not combined with any lamps on the rpm instrument. This case is not described in the owners manual. What could be the reason for the high idle speed and what does the buzzer tell me when it beeps "alone".

The motor has been out in freezing conditions for a couple of weeks. Thats why I changed battery. the capacity was ti low in cold weather.

Its a DF150 year 2007.

[catacom225]

When the idle exceeds 1000rpm an alarm code sounds [ single beep ]
Adjust air idle screw to 650rpm, then rev engine to over 1000rpm to cancel code

[orohde]

Thanks, now I need to locate the screw. It is not indicated in the owners manual. Is the screw easy to find?

The idle speed has been good the whole season. Any teory on why it came to be so serious so suddently that it now needs some screw adjustments?

[catacom225]

Remove the front air box and it will be above the air intake

[orohde]

Thanks, I will go and try this. I'll be back with a report

[z21832086]

do not mess with the idle air screw!...go inspect the white battery sub lead- fuse, condition, and connection to the battery

[orohde]

I checked the connection and it looked good. I did not have any instrument to measure conectivity so I tested by disconnecting the lead when the motor was running. It stopped, so I guess this is perhaps not the source of the high idle speed.

I am still reluctant to make any idle screw adjustment because I do not know of any good reason it has been removed from its "proper" position.

What else could lead to a sudden increase in idle speed. Something must have been broken either in connection with the battery change or during the freezing cold conditions.

[catacom225]

Orohde
You might try removing thr IAC valve and cleaning the air passage there may be an air flow restriction

[orohde]

The IAC valve was deformed, like if was hammered. This led to the sitiuation where even when the engine computer ordered full closure on the IAC there was still air available. The amount of air trespassing was high enough to keep the engine running at 1300rpm. I changed the valve, but we still could not get the idle speed below 800rpm, which indicates that the surface (IAC valve seat) on the intake manifold also was distorted. This means I have to buy a new IAC valve stepping motor and a new intake manifold, grrrrrrrrrrr!!!!$$$$$

Now that the reason for high idle speed is identified, I wonder how the valve could be destroyed like this. Any idea folks??

[catacom225]

I the same IAC valve from a Suzuki auto wrecker, and why not see if a machine shop can resurface your manifold or block it flat yourself