Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   496 mag ho suspicious performance (https://www.offshoreonly.com/forums/general-q/379500-496-mag-ho-suspicious-performance.html)

TomZ 06-07-2023 08:38 AM

If you're going to keep it for a while, buy the scan tool. Rinda Technologies - you'll be able to troubleshoot it easily.

253 06-07-2023 09:01 AM

Years ago my 496 Ho did the same thing,,,Remove the air intake screen just above the serpantine belt, the belt ,,dust,, sucks directly into the air intake, no mechanic could find the problem, after 4 weeks of derating engine, I removed the intake screen and it was full of belt dust, starving the engine for air,,after cleaning the intake screen it was perfect again,,just sayin check the small stuff.

techman 06-07-2023 09:46 AM


Originally Posted by 253 (Post 4869866)
Years ago my 496 Ho did the same thing,,,Remove the air intake screen just above the serpantine belt, the belt ,,dust,, sucks directly into the air intake, no mechanic could find the problem, after 4 weeks of derating engine, I removed the intake screen and it was full of belt dust, starving the engine for air,,after cleaning the intake screen it was perfect again,,just sayin check the small stuff.

While you are doing that...check the IAC muffler too. Those can get gunked up or worse sucked into the intake.

F-2 Speedy 06-07-2023 10:03 AM

Id guess water pressure alarm......sea pump might need a overhaul.

Outlawmarc 06-07-2023 12:14 PM

Filter was cleaned two weeks ago … brand new stainless hardin marine pump was also installed two weeks ago … brand new plug new oils … lot of things here are eliminated … idle is perfect engine starts really well …

BBYSTWY 06-07-2023 12:38 PM

Is it bouncing off the rev limiter? I haven't messed with one in awhile but I think the limiter will sound an alarm and pull RPM after so many times hitting it I think...could be wrong tho like I said been awhile lol

Outlawmarc 06-07-2023 12:40 PM

All rpm parameters seems to be on point … no bouncing and never hit rev limiter… just a 2 beep alarm … then sound like a loss of power afterward … im scanning it this weekend will keep you guys posted on this one .

BBYSTWY 06-07-2023 12:42 PM

I'm still thinking water pump actually....I know you said it's new but I think those have a flow and temp sensor for the water and you may not be getting the flow it wants or bad sensor or clogged sensor/line....keep us posted good luck!

techman 06-07-2023 12:50 PM

The two beep alarm is the equivalent of a car's "check engine" light. Your guessing until you scan it. Hopefully it doesn't become a "change engine" light.

Outlawmarc 06-07-2023 12:50 PM

Youre right on this one and this is what i assume also … pump is doing really fine mechanically but maybe a pressure/temp sensor failure here …


All times are GMT -5. The time now is 12:39 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.