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Old 06-16-2010 | 12:11 PM
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Default 496 Poppin through exhaust

I recently had a new 375 horse 496 installed in my Velocity, it has about 16 hours on it, I'm getting a popping out of the port side exhaust, predominately over 1500 rpm. It sounds like a misfire of some sort, any idea where to start looking?
Thanks in advance!!
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Old 06-16-2010 | 06:46 PM
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Compression test. stuck valve?
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Old 06-16-2010 | 09:09 PM
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Are you getting any alarms? I'd start by getting it scanned.

Is it under warranty?
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Old 06-16-2010 | 09:25 PM
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Firing order? Might not throw an alarm.Crank sensor maybe how does it run when its not doing it if it runs good doubt its internal but it needs to go on a scanner ASAP the laptop program is better.
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Old 06-16-2010 | 11:00 PM
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could be a broken rocker arm or a bent push rod..
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Old 06-17-2010 | 04:59 AM
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Simple things first, make sure the plug wires are on the correct cylinders on that side. If plug wiring is right check under the valve cover for as someone else said a bent pushrod or rocker arm issue. If that does not do it , check the compression of the cylinders on that side and see if ones way down, indicating a stuck or bent exhaust valve.
Hope its something simple.

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Ray @ Raylar
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Old 06-17-2010 | 06:01 AM
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Bad plugs, Carbs set wrong or dirty. Or even bad gas from sitting
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Old 06-17-2010 | 02:54 PM
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Originally Posted by 007joe
I recently had a new 375 horse 496 installed in my Velocity, it has about 16 hours on it, I'm getting a popping out of the port side exhaust, predominately over 1500 rpm. It sounds like a misfire of some sort, any idea where to start looking?
Thanks in advance!!
Cracked spark plug. Replace the plugs, see if it goes away. Went through the same thing on my dads 496.
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Old 06-17-2010 | 03:14 PM
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Thanks guys!!
To answer some questions I haven't gotten any alarms. It seems to run okay at higher rpms but not perfect. There is no warranty on the engine, and the shop that did it is about an hour and a half away and honestly left a bad taste in my mouth so rather bring it elsewhere or fix myself. Learned alotta lessons on this engine replacement.
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Old 06-17-2010 | 03:15 PM
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oh and what is the order the plug wires should be in? Thanks again!!
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