What is going on with my engine?

[66pony]

It seems that after sitting for a week or so, my engine starts fine, but when the throttle is applied, it seems to miss. I get maybe 2300 RPM out of it and it runs rough. There is definately a gasoline smell to the exhaust. After about 3-4 minutes it begins to smooth out and then runs better. I still am not able to get up to max RPM though. For the rest of the time it starts and runs OK. Still not able to get max RPM though. I could when it was new.
Is it ignition or injectors?

Thanks

 

[jason78]

It seems that after sitting for a week or so, my engine starts fine, but when the throttle is applied, it seems to miss. I get maybe 2300 RPM out of it and it runs rough. There is definately a gasoline smell to the exhaust. After about 3-4 minutes it begins to smooth out and then runs better. I still am not able to get up to max RPM though. For the rest of the time it starts and runs OK. Still not able to get max RPM though. I could when it was new.
Is it ignition or injectors?

Thanks

When was the last time you changed the Plugs, Cap and Rotor? If it has been more than a couple years, I would try those things with the cap and rotor being first. I have changed a number of them for friends to solve a bunch of different issues similar to this and I am always surprised how quick corrosion builds up on the terminals under the cap, causing issues, even though we are on a lake.

 

[hottoddie]

The misfire is the reason you smell gas. It is unburned fuel exiting the exhaust. Eliminate the misfire and you eliminate the smell of gas. I would follow Jason's advise and there is a good chance you will solve the issue. BTW make sure you use marine cap, rotor and plugs.

 

[66pony]

When was the last time you changed the Plugs, Cap and Rotor? If it has been more than a couple years, I would try those things with the cap and rotor being first. I have changed a number of them for friends to solve a bunch of different issues similar to this and I am always surprised how quick corrosion builds up on the terminals under the cap, causing issues, even though we are on a lake.

On the 496, there is not cap and rotor it has a fully electronic ignition. Thus we are changing plugs, but wanted to make sure it has no other sources of issues. the current plugs have 100 hours on them.

 

[scoflaw]

If the new plugs don't do it, check your fuel pressure next. High pressure caused by flaking paint is common

 

[jason78]

On the 496, there is not cap and rotor it has a fully electronic ignition.

Yep, sorry. Did not notice your details.