Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

2015 23 LSV Vibration

Recommended Posts

2015 23 LSV:

First day on the water this year.

Engine starts and sounds great. However, I notice a vibration between 1500 and 2000 rpm with the boat in gear. In neutral I feel no vibration. So its either the engine under load or something else. Prop looks great and I haven't hit anything. 1/2 of the tank is fresh fuel. The other half is last years tank with fuel stabilizer.

Second point, I swear the exhaust smells stronger this year and has an odor of unburned gasoline. 

Third factor, I was idling the engine in neutral and running the RPMs up the check the engine temp. While I was doing this I got a service required message: O2AFuelTrimLong DATA VALID BUT ABOVE NORMAL

SPN:4237 FML:0

I had this game message last season. Found the O2 sensors on the CATS were only finger tight. I secured them and never saw the message again. Until today.

Engine is L96 410

At first I was thinking it was a missing cylinder. However, I think if the cylinder was not firing it would sound really rough at idle. Not the case. Runs smooth in idle and revving rpm in neutral.

Smell of gas in exhaust lead me to think I had a cylinder not firing though.

All three factors may be separate issues. The vibration isn't bad. My other family members didn't even notice it until I pointed it out. 

Perhaps a Drive issue? But that wouldn't explain the gas smell.

I hate to take the boat to the shop (Im sure backlog is 3 weeks) for something that I wonder is my imagination.




Edited by MWJ68
Link to comment


I checked my past post. Found that the O2 sensor issue was different than todays.

Last year it was:  O2BFuelTrimLong DATA VALID BUT BELOW NORMAL

Tightened the O2 sensors and the problem didn't recur. 

That was last year.

Link to comment

Indmar came out with a better o2 for 6.0 boats. That’s a place to start. Also it’s worth pulling the o2s and checking for moistures. Those tube 6.0 headers are common for cracking and leaking water

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...