2002 Crownline 5.7

[Jamz33]

The customer stated that the boat would die (only sometimes) when he would bring the boat back to neutral. I checked it out and found it was loping (kind of like it was loading up) and ended up unplugging the idle air control valve and it never acted up after that. Naturally I thought the valve was bad so I replaced it and it still does the same thing. So I thought maybe the throttle position sensor so I replaced it and it still loped and died. I unplugged the idle air control valve (the new one) and it straightened up and runs fine. Any ideas? Thanks.

 

[ESGWheel]

I had a similar problem on my 2005 VP 5.0 GXi-E when I first got it. Kicked my butt and my local marina’s as well (neither of had scanners). Was taking a similar approach (shotgun parts) and eventually found my MAP sensor was all crapped up due to ‘belt dust’. Cleaned it up and ran perfect. Also tacked the belt dust issue and been fine for years now.

 

[Jamz33]

I had a similar problem on my 2005 VP 5.0 GXi-E when I first got it. Kicked my butt and my local marina’s as well (neither of had scanners). Was taking a similar approach (shotgun parts) and eventually found my MAP sensor was all crapped up due to ‘belt dust’. Cleaned it up and ran perfect. Also tacked the belt dust issue and been fine for years now.

I was unable to find the map sensor. I probably just overlooked it. I checked for vacuum leaks and I had no luck there. Again I could unplug the IACV and it ran perfect. I assumed if it had a vacuum leak that caused the erratic idle it would still do it even after I unplugged the IACV. Idk maybe not. I haven’t messed with very many throttle bodies.

 

[ESGWheel]

While your workaround may be working for now, I am sure you can appreciate that this is not the way to go. Best to find the issue and solve it. And I know this forum can help get you there.

I am unsure of your configuration. Best to post engine serial no. for those who can help better to be able to know what the specific of the engine are.

The MAP sensor on my 5.0 is located as shown the pic below > on the intake manifold aft of the intake.

 

[Jamz33]

While your workaround may be working for now, I am sure you can appreciate that this is not the way to go. Best to find the issue and solve it. And I know this forum can help get you there.

I am unsure of your configuration. Best to post engine serial no. for those who can help better to be able to know what the specific of the engine are.

The MAP sensor on my 5.0 is located as shown the pic below > on the intake manifold aft of the intake.

View attachment 410952

Thank you. I’m going to clean it tonight with some MAF cleaner and see what happens.

 

[Jamz33]

While your workaround may be working for now, I am sure you can appreciate that this is not the way to go. Best to find the issue and solve it. And I know this forum can help get you there.

I am unsure of your configuration. Best to post engine serial no. for those who can help better to be able to know what the specific of the engine are.

The MAP sensor on my 5.0 is located as shown the pic below > on the intake manifold aft of the intake.

View attachment 410952

And yes I want to find the problem instead of mask the problem.