Mercruiser 6.2's port runs rich

[Dlidds]

At start up my port leaves unburned fuel and a slight light smoke. Everything on computer reads within range. idle drops quick to 650 and flow is less than starboard. Changed: fuel cool modules, fuel injectors, plugs, wires. Runs great warm. What am I missing to get rid of this? Could it be:
1) muffler in throttle body ( no clue how to get to it?)
2) IAC sensor (whatever that is but Im told could cause)
3) Air filter, little sponge thing for $1.99?
Desperate to fix and enjoy without embarrassing smoke and fuel at dock.
thanks so much
Dlidds

 

[Bondo]

Ayuh,...... Welcome Aboard,......

I don't do the electronic motors, but I'm bettin' AlDodge might be able to help ya,.....
He's gonna want the serial number of the motor though,.....

 

[bruceb58]

At start up my port leaves unburned fuel and a slight light smoke. Everything on computer reads within range. idle drops quick to 650 and flow is less than starboard. Changed: fuel cool modules, fuel injectors, plugs, wires. Runs great warm. What am I missing to get rid of this? Could it be:
1) muffler in throttle body ( no clue how to get to it?)
2) IAC sensor (whatever that is but Im told could cause)
3) Air filter, little sponge thing for $1.99?
Desperate to fix and enjoy without embarrassing smoke and fuel at dock.
thanks so much
Dlidds

You are going to need to specify which 6.2 you have. The newer Merc 6.2 or the older GM 6.2.

 

[QBhoy]

Hi. If this is an mpi like I assume. Few things to say. I’d get a new iac sponge filter. They are pennies. Won’t do any harm. I’d also say that it’s normal for any mpi I’ve known to run rich for a wee bit after a cold start. They deliberately over fuel when cold. But if it’s excessive from your other engine, perhaps one of them isn’t acting normally. The temperature of the engine has a direct effect on the fuelling from the ecu.
without seeing how bad your issue is. Hard to tell. But if it’s blue smoke that’s a different matter. That’s burning oil and not fuel. If it’s a more grey or white looking smoke and definitely smells of fuel. It’s running rich as you say. All quite normal on an mpi. Within reason. I’m assuming you aren’t opening the throttle at all when you start your engines. You shouldn’t on these. If you do. They will defo throw some fuel out the back.

 

[bruceb58]

Would be nice to know which engine he has before we start troubleshooting.

 

[QBhoy]

Would be nice to know which engine he has before we start troubleshooting.

I’m assuming it’s a 6.2 mpi GM. Given the “computer”, “IAC” “IAC filter”. Can’t think of another apart from the brand new 6.2 that Will be a little different.
trying to help the guy out here and make is easy on him

 

[bruceb58]

I’m assuming it’s a 6.2 mpi GM. Given the “computer”, “IAC” “IAC filter”. Can’t think of another apart from the brand new 6.2 that Will be a little different.
trying to help the guy out here and make is easy on him

Exactly....want to know if it's the new engine introduced in 2016 or not.

 

[QBhoy]

Exactly....want to know if it's the new engine introduced in 2016 or not.

Fair play Bruce.

 

[Dlidds]

Hi. If this is an mpi like I assume. Few things to say. I’d get a new iac sponge filter. They are pennies. Won’t do any harm. I’d also say that it’s normal for any mpi I’ve known to run rich for a wee bit after a cold start. They deliberately over fuel when cold. But if it’s excessive from your other engine, perhaps one of them isn’t acting normally. The temperature of the engine has a direct effect on the fuelling from the ecu.
without seeing how bad your issue is. Hard to tell. But if it’s blue smoke that’s a different matter. That’s burning oil and not fuel. If it’s a more grey or white looking smoke and definitely smells of fuel. It’s running rich as you say. All quite normal on an mpi. Within reason. I’m assuming you aren’t opening the throttle at all when you start your engines. You shouldn’t on these. If you do. They will defo throw some fuel out the back.

2007 6.2L MPI, sorry for not confirming. Starboard is fine. I have changed cool fuel modules, plugs and tune up shows nothing.
Im told that IAC may be it for $1.99 on this stream. Also s there a cap or ? I see theres a tune up kit and cap. Appreciate any help .

 

[Dlidds]

Exactly....want to know if it's the new engine introduced in 2016 or not.

thank you...

 

[Dlidds]

Would be nice to know which engine he has before we start troubleshooting.

 

[Dlidds]

I have 2007 320DA 6.2L .

At start up my port leaves unburned fuel and a slight light smoke. Everything on computer reads within range. idle drops quick to 650 and flow is less than starboard. Changed: fuel cool modules, fuel injectors, plugs, wires. Runs great warm. What am I missing to get rid of this? Could it be:
1) muffler in throttle body ( no clue how to get to it?)
2) IAC sensor (whatever that is but Im told could cause)
3) Air filter, little sponge thing for $1.99?
Desperate to fix and enjoy without embarrassing smoke and fuel at dock.
thanks so much
Dlidds

 

[Dlidds]

Does this help?

 

[Bondo]

Does this help?

He's gonna want the serial number of the motor though,.....

Ayuh,..... The '06 date probably helps some, but the serial number is kinda important, especially for the electronic motors,.....

 

[Dlidds]

You are going to need to specify which 6.2 you have. The newer Merc 6.2 or the older GM 6.2.

Merc 6.2 ... boats a 2007

 

[Dlidds]

Ayuh,...... Welcome Aboard,......

I don't do the electronic motors, but I'm bettin' AlDodge might be able to help ya,.....
He's gonna want the serial number of the motor though,.....

I have them. Can you DM me for his number ? or link? thanks so much

 

[Dlidds]

Hi. If this is an mpi like I assume. Few things to say. I’d get a new iac sponge filter. They are pennies. Won’t do any harm. I’d also say that it’s normal for any mpi I’ve known to run rich for a wee bit after a cold start. They deliberately over fuel when cold. But if it’s excessive from your other engine, perhaps one of them isn’t acting normally. The temperature of the engine has a direct effect on the fuelling from the ecu.
without seeing how bad your issue is. Hard to tell. But if it’s blue smoke that’s a different matter. That’s burning oil and not fuel. If it’s a more grey or white looking smoke and definitely smells of fuel. It’s running rich as you say. All quite normal on an mpi. Within reason. I’m assuming you aren’t opening the throttle at all when you start your engines. You shouldn’t on these. If you do. They will defo throw some fuel out the back.

Definintely white, light grey and fuel smell. Compression tests and engines run great per Merc computer.
thx!! Ill keep digging

 

[Dlidds]

Would be nice to know which engine he has before we start troubleshooting.

2007 sea ray 320 DA , Mercruiser 6.2l engines

 

[alldodge]

Hey Dilidds, knock, knock is anyone home??? You have been ask a few times about the number
We need to know what your serial number is?

Looks like the serial number might be on the tag on the plastic cover in your pic.

With fuel getting in the water I'm wondering if the fuel cooler has a leak. In your fist post you have said the cooler has been replaced

 

[alldodge]

The serial number is a number, letter and then 6 numbers
Exp 1A123456 or 0W123456