Suzuki 140hp 2012 stalling

[Bee888]

Hi redlowrey,

Thanks, that makes more sense.
I tested with it left on and had about 6.3v with throttle open, 0v with closed. Assuming my cheap tester isnt extremly accurate Id say this is Ok.

My local mechanic is mobile and came around today.
We popped it onto his laptop he has with the SDS software and tried the IAC bypass adjustment. Results below:


Before started
IAC was around 35% duty. Idling between 6 to 800.

Did air by pass procedure according to manual.
Turned bypass screw counter clockwise and Held rpm at 1000 for over 10 secs and slow beep started to indicate IAC should be at 15%, but IAC wouldnt drop below 29%.

With the slow beep every 3 secs running, the IAC never hit 15%. We left it there for a while and didnt happen. So ended up turning back down the idling and cancelling the operation by lifting the fast idle leaver.

Idling now at 688 to 720 with IAC duty at 33/33%.

Does the fact the IAC duty was supposed to be fixed at 15% and didnt occur mean a bad ECM?

[Bee888]

Just re-read your previous responses and noticed you had mentioned the IAC would be fixed at 30% duty. The manual off a 2008 jad specificed it would be fixed at 15% which was the confusion.

Did it change for 2012 model?

[Bee888]

Put it in the water after the idle reset and tested again. Was much better! I was only able to get it to stall twice.

Once by quickly throttling in reverse it stalled, and the other after about 50 attempts of advancing forward and pulling back throttle quickly. Previously I could get it to stall doing this all the time.

Put it back on the laptop on it again.
And everything appears normal, the motor idles stable and sits between 688 to 720rpm. Also put it in the water under load and connected the computer - same results.

Upon starting idle jumps to around 850rpm, IAC 37/38%. After warm drops to spec and IAC is around 33%.

Looks to me like ECM and IAC duty is all normal.

For the two times that it stalled, I believe it is due to my cables being stretched. In reverse I found there's there's point a with the throttle closed, that the ctp switch has no continuity. I adjusted the turn buckle on the throttle cable 2 more turns in (all thread is in and none left) and its now as far as I could go.

That adjustment has now given me contuity at the ctp switch through the reverse in gear idle position, but there is still a tiny point just before throttle opens that it is lost. I'll test the boat again. If it still stalls in reverse, I will be replacing my throttle cables with some new ones.

Anything else you guys think I should check will be great. Thanks for the help so far.