# 2003 Suzuki DF115 - IAC Valve



## Brad from Bagdad (Oct 2, 2007)

Guys,
I took my boat into the mechanic because it was idling rough and the 3-1 check engine light/MIL code. They stated that they had hooked it up to their computers and determined the IAC valve was bad. He indicated that often times they can remove the IAC valve, give it a thorough cleaning, and reinstall it. So, we took this route and of course the boat idled beautifully in the parking lot and the check engine light quit flashing. Well, 30 minutes later I crank it up at my house and the code is back flashing again with the same 3-1 check engine light/MIL code. I'm guessing that means the IAC valve needs complete replacing?? Has anybody else faced this issue? I hate to spend $281 on a part that I'm not 100% sure is the cause of my issues. As best I can tell, I can easily remove and replace the IAC valve myself. Please correct me if I'm wrong. Thanks for any input.


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## feelin' wright (Oct 7, 2007)

First thing I would check would be to remove the cowling and see if this stops the error light from flashing. If it does then you have a corroded plug on the engine

Suzuki had a defect in their mid to late 2000s engines to where they put a steel plug on the engine holder which is aluminum. This causes the plug to rust and you get exhaust into the cowling which causes the IAC valve to error out. The plug can be seen once you remove the lower cowling. It will be on the lower left hand side of the engine. If this is the case you need to get it fixed immediately. If the plug corrodes bad enough the exhaust gases will melt the wiring harness and then spike your computer and then you are looking at 2000.00 in repairs before you fix the engine holder problem. If this is the case then you have two ways to fix it. 

1. Replace the entire engine holder assembly which is expensive (1000) for parts and then you have to disassemble the engine. 
2. Take the boat to so machine shop and have them remove the plug and weld it back together. I have a guy that lives down the street that welded mine together. 

I live just down the street in milton across from Benny Russel Elementary if you want to drag it over I can show you where the corroded plug will be.


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## Brad from Bagdad (Oct 2, 2007)

Thanks Feelin' Wright. When I get home, I'll remove the cowling and see if this resolves my issues. I live right off of Avalon, so I definitely may be stopping by. If I have the plug issue you're referring to, I may need to get in touch with your buddy that welded yours. Thanks


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## feelin' wright (Oct 7, 2007)

No problem. I have PM'd you my contact information. Think he charged me 50 bucks to weld it closed. I will be home all evening drinking beer & telling lies about fishing.


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## caylorray (Oct 3, 2007)

Just to validate what's been said...

My 04 DF90 experienced this exact same thing. Took me 2 years to figure it out. Had mine welded back up and it's been running like a champ since. 

Here's a link that illustrates this problem quite well:

http://www.thehulltruth.com/boating-forum/395845-suzuki-df140-engine-holder-corrosion-fix.html

Also, Google "suzuki engine holder corrosion" and you'll come across all kinds of information about this issue.


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