Idle adjustment for Marine Power engine

[Jetter]

Sorry this may be a dumb questions but does anyone know if idle adjustment can only be done using a computer and Rinda Diacom? My boat (08 Z1) idles way too low in the neighborhood of 450-500 rpm and will sometimes stall out when you pop it into gear. If I put in in neutral and adjust the throttle slightly it purrs much better in the 800-900 range. What is a normal idle for these? Again my motor is an 08 Marine Power 360HT. Thanks.

[chpthril]

Nope, the idle is controlled by the program. I would first start with removing the IAC and giving it and the throttle body a good cleaning with carb cleaner spray and compressed air. Also clean the flame arrester.

[Jetter]

Nope, the idle is controlled by the program. I would first start with removing the IAC and giving it and the throttle body a good cleaning with carb cleaner spray and compressed air. Also clean the flame arrester.

Thanks Mike. The throttle body is brand new as of last season but I will do that nonetheless. I guess I'll have to take it to the marine dealer in the spring.

[chpthril]

Was the IAC new or at least cleaned? It may be stuck. Do you know if the minimum air rate was set when the t-body was installed? Sounds like the engine is idling at the minimum, and the IAC is not operating.

On a road vehicle, the scan tool lets you see desired and actual RPM, and they should be close. You can also see an IAC value, as well as control the IAC to test its operation. I would imagine the MEFI would allow the same.

[Jetter]

No it wasn't cleaned or replaced. I seem to recall us just removing the old throttle body and replacing it with the new. Would the IAC have been part of the new throttle body or would it have been unplugged and plugged into the new? Hmmm.. Now you got me thinking. I still have the old throttle body - I'll check.

[chpthril]

Would the IAC have been part of the new throttle body

Although its a separate component, a new one could been part of the replacement t-body. You would have had to unscrew the old one and transfer it over to the new body from the old. If it was included, you would have just been the plug to pop off and reconnect to the new one. I think its a 4 wire flat connector.

[Jetter]

Although its a separate component, a new one could been part of the replacement t-body. You would have had to unscrew the old one and transfer it over to the new body from the old. If it was included, you would have just been the plug to pop off and reconnect to the new one. I think its a 4 wire flat connector.

I'm pretty sure it was a plug pop off and reattach. I will check later today. The idle was low prior to the original throttle body dying so I'm hoping it's a computer thing. I will have them check the IAC as well in the spring.