2005 DF250 CKP sensor and IAC valve failure

[Dive4lobster]

I've got a triple set of 2005 DF250's. The starboard motor requires a fair amount of neutral throttle to get her started, once warmed up and brought back to neutral she dies. The Suzuki download shows a CKP sensor failure of 24 times and an IAC valve failure of 13 times. I'm getting an audible check engine alarm on the tach as well. Searching the Internet for the CKP sensor I've come up short. I'm ordering a service manual, but thought maybe you guys could give me some guidance. I'd like to rotate the two sensors from the center engine to see if that clears the codes.
Thanks
dive4lobster

[Moonlighter]

Most likely the IAC valve failure. If you search this forum (only the advanced search works) you will find details including where to buy suitable replacement part which is identical to OEM but much less expensive.

Here is one link with some inf:

http://www.thehulltruth.com/boating-...f140-help.html

Check the part number, but I am reasonably certain that the part is made by Mitsubishi for Suzuki, and you can buy the Mitsubish part for a fraction of the price of the Suzuki branded version which goes for over $300 see:

http://www.ebay.com.au/itm/Brand-New...-/111500122372

[artdf175]

to add to what Grant mentioned
yes you can interchange parts from one motor to the other
you have the advantage of having multiple motors to cross check parts to see if they are working or not

Art

[Dive4lobster]

Update.. Rotated iac valve from known good engine. Problem solved. I found three on eBay for around 35 dollars a piece.

Now new problem, the center engine idles around 1500. I switched back to an old iac valve to make sure I didn't get a defective unit but still no change. I did also change the t stats as well..

[artdf175]

with an investment in 3 motors - I can only highly recommend getting the full service manual for your year and model will save you a bunch of $$
will try to look later today .. there should be only a couple of reasons the motor does not idle back correctly shortly after starting

another way to see if it maybe a part vs the ECM would be to swap one of the
ECM's if RPM drops back to normal .. it would be potentially a bad ECM
If it doesn't then one of the of other sensors is not reading correctly\

[Moonlighter]

There is a reset procedure for the IAC that should, I think, be in the owners manual, I have seen references to it elsewhere. This gets the idle speed back to normal.

Sounds like you need to complete that procedure.

[Dive4lobster]

I have the full service manual for the engines and saw where there is a way to adjust IAC valve duty and idle speeds by turning the by pass air screw clockwise on the port throttle body. When I do this there is no change to the Rpms when turning the screw clockwise. I checked for any loose vacuum lines and I also rotated ECM from starboard motor. Still no change idles close to 2k now.

Any other troubleshooting ideas?