4.3EFI stalls in neutral when hot

[SandyBoat]

I?m having a problem with my 2001 Mercruiser 4.3EFI. The engine starts and runs fine when on the flush muffs and runs perfectly when out on the water. The only problem is, when I?m out on the water and stop and put the boat into neutral the engine sometimes stalls. The alarm sounds as it cuts out. The engine will then restart without a problem.

This also happens when I am back on dry land and try and run the boat on the flush muffs. Starts fine, then cuts out. As soon as I start it and give it some revs in neutral, it is then fine.

Any ideas? Seems to me that the problem is only happening when the engine is hot from being worked.

Thx for any suggestions.

 

[SandyBoat]

Re: 4.3EFI stalls in neutral when hot

Any ideas anyone?

 

[180shabah]

Re: 4.3EFI stalls in neutral when hot

Any combination of the following:
Shift cable
bad MAP sensor
coolant temp sensor
desparate need of a tune up
sticking IAC
etc.
etc.

 

[SandyBoat]

Re: 4.3EFI stalls in neutral when hot

Thanks for the reply.

Shift cable? You think the shift interupter maybe operating? Or some other problem here?

Would any of these show up as faults if I read the fault codes?
bad MAP sensor
coolant temp sensor
sticking IAC

Finally, where would you start looking?

Thx

 

[Bondo]

Re: 4.3EFI stalls in neutral when hot

Shift cable? You think the shift interupter maybe operating? Or some other problem here?

Ayuh,... At 8 years old,... That's My 1st thought...

 

[SandyBoat]

Re: 4.3EFI stalls in neutral when hot

Re the shift interrupter - when I run the boat on the flush muffs after I have been out on the water, it starts ok, then cuts out. Surely if the shift interrupter was not working properly it wouldn't start at all as it cuts the ignition?

 

[Bondo]

Re: 4.3EFI stalls in neutral when hot

when I run the boat on the flush muffs after I have been out on the water, it starts ok, then cuts out.

Ayuh,... I guess if it does that without Shifting it,.... I'm Wrong....

Sorry,... It's not the 1st time....

 

[SandyBoat]

Re: 4.3EFI stalls in neutral when hot

Yes, starts fine in neutral and then cuts out, without touching the throttle/gear change. It only does this on the flush muffs after I have been out on the water, ie when it is hot from use. I have not been able to get the engine to cut out when running it on flush muffs from cold. Its almost as if its run out of fuel, with just enough in the pipes to get it started.

 

[Don S]

Re: 4.3EFI stalls in neutral when hot

Do you have an Alpha or Bravo drive? The 4.3EFI use both.

 

[JustJason]

Re: 4.3EFI stalls in neutral when hot

Aside from the drive question.... when was the last time the boat had a complete tune up?

 

[SandyBoat]

Re: 4.3EFI stalls in neutral when hot

Thanks for the comments. The outdrive is an Alpha 1 Gen II. The engine last had a tune-up a couple of months ago when I serviced it. I am thinking that I should go through the tune-up again and check everything I did and see if I missed anything.

Aside from this problem the boat is running great, so I'm not too concerned, but would of course like to have it working perfectly.